# HG changeset patch # User Matt Johnston # Date 1468337595 -28800 # Node ID 8678e2cc1e5370d62f0d17a1809de3f428aeb7e7 # Parent ad9c40aca3bcbe49a7876243d35196a08a4f14a7 make indenting consistent diff -r ad9c40aca3bc -r 8678e2cc1e53 keyimport.c --- a/keyimport.c Tue Jul 12 23:28:42 2016 +0800 +++ b/keyimport.c Tue Jul 12 23:33:15 2016 +0800 @@ -47,15 +47,15 @@ (cp)[0] = (unsigned char)((value) >> 24); } while (0) #define GET_32BIT(cp) \ - (((unsigned long)(unsigned char)(cp)[0] << 24) | \ - ((unsigned long)(unsigned char)(cp)[1] << 16) | \ - ((unsigned long)(unsigned char)(cp)[2] << 8) | \ - ((unsigned long)(unsigned char)(cp)[3])) + (((unsigned long)(unsigned char)(cp)[0] << 24) | \ + ((unsigned long)(unsigned char)(cp)[1] << 16) | \ + ((unsigned long)(unsigned char)(cp)[2] << 8) | \ + ((unsigned long)(unsigned char)(cp)[3])) static int openssh_encrypted(const char *filename); static sign_key *openssh_read(const char *filename, char *passphrase); static int openssh_write(const char *filename, sign_key *key, - char *passphrase); + char *passphrase); static int dropbear_write(const char*filename, sign_key * key); static sign_key *dropbear_read(const char* filename); @@ -66,118 +66,118 @@ static int sshcom_encrypted(const char *filename, char **comment); static struct ssh2_userkey *sshcom_read(const char *filename, char *passphrase); static int sshcom_write(const char *filename, struct ssh2_userkey *key, - char *passphrase); + char *passphrase); #endif int import_encrypted(const char* filename, int filetype) { - if (filetype == KEYFILE_OPENSSH) { - return openssh_encrypted(filename); + if (filetype == KEYFILE_OPENSSH) { + return openssh_encrypted(filename); #if 0 - } else if (filetype == KEYFILE_SSHCOM) { - return sshcom_encrypted(filename, NULL); + } else if (filetype == KEYFILE_SSHCOM) { + return sshcom_encrypted(filename, NULL); #endif - } - return 0; + } + return 0; } sign_key *import_read(const char *filename, char *passphrase, int filetype) { - if (filetype == KEYFILE_OPENSSH) { - return openssh_read(filename, passphrase); - } else if (filetype == KEYFILE_DROPBEAR) { - return dropbear_read(filename); + if (filetype == KEYFILE_OPENSSH) { + return openssh_read(filename, passphrase); + } else if (filetype == KEYFILE_DROPBEAR) { + return dropbear_read(filename); #if 0 - } else if (filetype == KEYFILE_SSHCOM) { - return sshcom_read(filename, passphrase); + } else if (filetype == KEYFILE_SSHCOM) { + return sshcom_read(filename, passphrase); #endif - } - return NULL; + } + return NULL; } int import_write(const char *filename, sign_key *key, char *passphrase, - int filetype) { + int filetype) { - if (filetype == KEYFILE_OPENSSH) { - return openssh_write(filename, key, passphrase); - } else if (filetype == KEYFILE_DROPBEAR) { - return dropbear_write(filename, key); + if (filetype == KEYFILE_OPENSSH) { + return openssh_write(filename, key, passphrase); + } else if (filetype == KEYFILE_DROPBEAR) { + return dropbear_write(filename, key); #if 0 - } else if (filetype == KEYFILE_SSHCOM) { - return sshcom_write(filename, key, passphrase); + } else if (filetype == KEYFILE_SSHCOM) { + return sshcom_write(filename, key, passphrase); #endif - } - return 0; + } + return 0; } static sign_key *dropbear_read(const char* filename) { - buffer * buf = NULL; - sign_key *ret = NULL; - enum signkey_type type; + buffer * buf = NULL; + sign_key *ret = NULL; + enum signkey_type type; - buf = buf_new(MAX_PRIVKEY_SIZE); - if (buf_readfile(buf, filename) == DROPBEAR_FAILURE) { - goto error; - } + buf = buf_new(MAX_PRIVKEY_SIZE); + if (buf_readfile(buf, filename) == DROPBEAR_FAILURE) { + goto error; + } - buf_setpos(buf, 0); - ret = new_sign_key(); + buf_setpos(buf, 0); + ret = new_sign_key(); - type = DROPBEAR_SIGNKEY_ANY; - if (buf_get_priv_key(buf, ret, &type) == DROPBEAR_FAILURE){ - goto error; - } - buf_free(buf); + type = DROPBEAR_SIGNKEY_ANY; + if (buf_get_priv_key(buf, ret, &type) == DROPBEAR_FAILURE){ + goto error; + } + buf_free(buf); - ret->type = type; + ret->type = type; - return ret; + return ret; error: - if (buf) { - buf_free(buf); - } - if (ret) { - sign_key_free(ret); - } - return NULL; + if (buf) { + buf_free(buf); + } + if (ret) { + sign_key_free(ret); + } + return NULL; } /* returns 0 on fail, 1 on success */ static int dropbear_write(const char*filename, sign_key * key) { - buffer * buf; - FILE*fp; - int len; - int ret; + buffer * buf; + FILE*fp; + int len; + int ret; - buf = buf_new(MAX_PRIVKEY_SIZE); - buf_put_priv_key(buf, key, key->type); + buf = buf_new(MAX_PRIVKEY_SIZE); + buf_put_priv_key(buf, key, key->type); - fp = fopen(filename, "w"); - if (!fp) { - ret = 0; - goto out; - } + fp = fopen(filename, "w"); + if (!fp) { + ret = 0; + goto out; + } - buf_setpos(buf, 0); - do { - len = fwrite(buf_getptr(buf, buf->len - buf->pos), - 1, buf->len - buf->pos, fp); - buf_incrpos(buf, len); - } while (len > 0 && buf->len != buf->pos); + buf_setpos(buf, 0); + do { + len = fwrite(buf_getptr(buf, buf->len - buf->pos), + 1, buf->len - buf->pos, fp); + buf_incrpos(buf, len); + } while (len > 0 && buf->len != buf->pos); - fclose(fp); + fclose(fp); - if (buf->pos != buf->len) { - ret = 0; - } else { - ret = 1; - } + if (buf->pos != buf->len) { + ret = 0; + } else { + ret = 1; + } out: - buf_free(buf); - return ret; + buf_free(buf); + return ret; } @@ -186,31 +186,31 @@ */ #define isbase64(c) ( ((c) >= 'A' && (c) <= 'Z') || \ - ((c) >= 'a' && (c) <= 'z') || \ - ((c) >= '0' && (c) <= '9') || \ - (c) == '+' || (c) == '/' || (c) == '=' \ - ) + ((c) >= 'a' && (c) <= 'z') || \ + ((c) >= '0' && (c) <= '9') || \ + (c) == '+' || (c) == '/' || (c) == '=' \ + ) /* cpl has to be less than 100 */ static void base64_encode_fp(FILE * fp, unsigned char *data, - int datalen, int cpl) + int datalen, int cpl) { - unsigned char out[100]; - int n; - unsigned long outlen; - int rawcpl; - rawcpl = cpl * 3 / 4; - dropbear_assert((unsigned int)cpl < sizeof(out)); + unsigned char out[100]; + int n; + unsigned long outlen; + int rawcpl; + rawcpl = cpl * 3 / 4; + dropbear_assert((unsigned int)cpl < sizeof(out)); - while (datalen > 0) { - n = (datalen < rawcpl ? datalen : rawcpl); - outlen = sizeof(out); - base64_encode(data, n, out, &outlen); - data += n; - datalen -= n; - fwrite(out, 1, outlen, fp); - fputc('\n', fp); - } + while (datalen > 0) { + n = (datalen < rawcpl ? datalen : rawcpl); + outlen = sizeof(out); + base64_encode(data, n, out, &outlen); + data += n; + datalen -= n; + fwrite(out, 1, outlen, fp); + fputc('\n', fp); + } } /* * Read an ASN.1/BER identifier and length pair. @@ -232,53 +232,53 @@ #define ASN1_CONSTRUCTED (1 << 5) static int ber_read_id_len(void *source, int sourcelen, - int *id, int *length, int *flags) + int *id, int *length, int *flags) { - unsigned char *p = (unsigned char *) source; + unsigned char *p = (unsigned char *) source; - if (sourcelen == 0) - return -1; + if (sourcelen == 0) + return -1; - *flags = (*p & 0xE0); - if ((*p & 0x1F) == 0x1F) { - *id = 0; - while (*p & 0x80) { - p++, sourcelen--; - if (sourcelen == 0) - return -1; - *id = (*id << 7) | (*p & 0x7F); + *flags = (*p & 0xE0); + if ((*p & 0x1F) == 0x1F) { + *id = 0; + while (*p & 0x80) { + p++, sourcelen--; + if (sourcelen == 0) + return -1; + *id = (*id << 7) | (*p & 0x7F); + } + p++, sourcelen--; + } else { + *id = *p & 0x1F; + p++, sourcelen--; } - p++, sourcelen--; - } else { - *id = *p & 0x1F; - p++, sourcelen--; - } - if (sourcelen == 0) - return -1; + if (sourcelen == 0) + return -1; - if (*p & 0x80) { - unsigned len; - int n = *p & 0x7F; - p++, sourcelen--; - if (sourcelen < n) - return -1; - len = 0; - while (n--) - len = (len << 8) | (*p++); - sourcelen -= n; - *length = toint(len); - } else { - *length = *p; - p++, sourcelen--; - } + if (*p & 0x80) { + unsigned len; + int n = *p & 0x7F; + p++, sourcelen--; + if (sourcelen < n) + return -1; + len = 0; + while (n--) + len = (len << 8) | (*p++); + sourcelen -= n; + *length = toint(len); + } else { + *length = *p; + p++, sourcelen--; + } - if (*length < 0) { - printf("Negative ASN.1 length\n"); - return -1; - } + if (*length < 0) { + printf("Negative ASN.1 length\n"); + return -1; + } - return p - (unsigned char *) source; + return p - (unsigned char *) source; } /* @@ -289,57 +289,57 @@ */ static int ber_write_id_len(void *dest, int id, int length, int flags) { - unsigned char *d = (unsigned char *)dest; - int len = 0; + unsigned char *d = (unsigned char *)dest; + int len = 0; - if (id <= 30) { - /* - * Identifier is one byte. - */ - len++; - if (d) *d++ = id | flags; - } else { - int n; - /* - * Identifier is multiple bytes: the first byte is 11111 - * plus the flags, and subsequent bytes encode the value of - * the identifier, 7 bits at a time, with the top bit of - * each byte 1 except the last one which is 0. - */ - len++; - if (d) *d++ = 0x1F | flags; - for (n = 1; (id >> (7*n)) > 0; n++) - continue; /* count the bytes */ - while (n--) { - len++; - if (d) *d++ = (n ? 0x80 : 0) | ((id >> (7*n)) & 0x7F); + if (id <= 30) { + /* + * Identifier is one byte. + */ + len++; + if (d) *d++ = id | flags; + } else { + int n; + /* + * Identifier is multiple bytes: the first byte is 11111 + * plus the flags, and subsequent bytes encode the value of + * the identifier, 7 bits at a time, with the top bit of + * each byte 1 except the last one which is 0. + */ + len++; + if (d) *d++ = 0x1F | flags; + for (n = 1; (id >> (7*n)) > 0; n++) + continue; /* count the bytes */ + while (n--) { + len++; + if (d) *d++ = (n ? 0x80 : 0) | ((id >> (7*n)) & 0x7F); + } } - } - if (length < 128) { - /* - * Length is one byte. - */ - len++; - if (d) *d++ = length; - } else { - int n; - /* - * Length is multiple bytes. The first is 0x80 plus the - * number of subsequent bytes, and the subsequent bytes - * encode the actual length. - */ - for (n = 1; (length >> (8*n)) > 0; n++) - continue; /* count the bytes */ - len++; - if (d) *d++ = 0x80 | n; - while (n--) { - len++; - if (d) *d++ = (length >> (8*n)) & 0xFF; + if (length < 128) { + /* + * Length is one byte. + */ + len++; + if (d) *d++ = length; + } else { + int n; + /* + * Length is multiple bytes. The first is 0x80 plus the + * number of subsequent bytes, and the subsequent bytes + * encode the actual length. + */ + for (n = 1; (length >> (8*n)) > 0; n++) + continue; /* count the bytes */ + len++; + if (d) *d++ = 0x80 | n; + while (n--) { + len++; + if (d) *d++ = (length >> (8*n)) & 0xFF; + } } - } - return len; + return len; } @@ -352,469 +352,469 @@ enum { OSSH_DSA, OSSH_RSA, OSSH_EC }; struct openssh_key { - int type; - int encrypted; - char iv[32]; - unsigned char *keyblob; - unsigned int keyblob_len, keyblob_size; + int type; + int encrypted; + char iv[32]; + unsigned char *keyblob; + unsigned int keyblob_len, keyblob_size; }; static struct openssh_key *load_openssh_key(const char *filename) { - struct openssh_key *ret; - FILE *fp = NULL; - char buffer[256]; - char *errmsg = NULL, *p = NULL; - int headers_done; - unsigned long len, outlen; - - ret = (struct openssh_key*)m_malloc(sizeof(struct openssh_key)); - ret->keyblob = NULL; - ret->keyblob_len = ret->keyblob_size = 0; - ret->encrypted = 0; - memset(ret->iv, 0, sizeof(ret->iv)); + struct openssh_key *ret; + FILE *fp = NULL; + char buffer[256]; + char *errmsg = NULL, *p = NULL; + int headers_done; + unsigned long len, outlen; - if (strlen(filename) == 1 && filename[0] == '-') { - fp = stdin; - } else { - fp = fopen(filename, "r"); - } - if (!fp) { - errmsg = "Unable to open key file"; - goto error; - } - if (!fgets(buffer, sizeof(buffer), fp) || - 0 != strncmp(buffer, "-----BEGIN ", 11) || - 0 != strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) { - errmsg = "File does not begin with OpenSSH key header"; - goto error; - } - if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n")) - ret->type = OSSH_RSA; - else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n")) - ret->type = OSSH_DSA; - else if (!strcmp(buffer, "-----BEGIN EC PRIVATE KEY-----\n")) - ret->type = OSSH_EC; - else { - errmsg = "Unrecognised key type"; - goto error; - } + ret = (struct openssh_key*)m_malloc(sizeof(struct openssh_key)); + ret->keyblob = NULL; + ret->keyblob_len = ret->keyblob_size = 0; + ret->encrypted = 0; + memset(ret->iv, 0, sizeof(ret->iv)); - headers_done = 0; - while (1) { - if (!fgets(buffer, sizeof(buffer), fp)) { - errmsg = "Unexpected end of file"; - goto error; + if (strlen(filename) == 1 && filename[0] == '-') { + fp = stdin; + } else { + fp = fopen(filename, "r"); + } + if (!fp) { + errmsg = "Unable to open key file"; + goto error; } - if (0 == strncmp(buffer, "-----END ", 9) && - 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) - break; /* done */ - if ((p = strchr(buffer, ':')) != NULL) { - if (headers_done) { - errmsg = "Header found in body of key data"; + if (!fgets(buffer, sizeof(buffer), fp) || + 0 != strncmp(buffer, "-----BEGIN ", 11) || + 0 != strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) { + errmsg = "File does not begin with OpenSSH key header"; goto error; - } - *p++ = '\0'; - while (*p && isspace((unsigned char)*p)) p++; - if (!strcmp(buffer, "Proc-Type")) { - if (p[0] != '4' || p[1] != ',') { - errmsg = "Proc-Type is not 4 (only 4 is supported)"; - goto error; - } - p += 2; - if (!strcmp(p, "ENCRYPTED\n")) - ret->encrypted = 1; - } else if (!strcmp(buffer, "DEK-Info")) { - int i, j; - - if (strncmp(p, "DES-EDE3-CBC,", 13)) { - errmsg = "Ciphers other than DES-EDE3-CBC not supported"; - goto error; - } - p += 13; - for (i = 0; i < 8; i++) { - if (1 != sscanf(p, "%2x", &j)) - break; - ret->iv[i] = j; - p += 2; - } - if (i < 8) { - errmsg = "Expected 16-digit iv in DEK-Info"; - goto error; - } - } - } else { - headers_done = 1; - len = strlen(buffer); - outlen = len*4/3; - if (ret->keyblob_len + outlen > ret->keyblob_size) { - ret->keyblob_size = ret->keyblob_len + outlen + 256; - ret->keyblob = (unsigned char*)m_realloc(ret->keyblob, - ret->keyblob_size); - } - outlen = ret->keyblob_size - ret->keyblob_len; - if (base64_decode((const unsigned char *)buffer, len, - ret->keyblob + ret->keyblob_len, &outlen) != CRYPT_OK){ - errmsg = "Error decoding base64"; - goto error; - } - ret->keyblob_len += outlen; - } + } + if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n")) + ret->type = OSSH_RSA; + else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n")) + ret->type = OSSH_DSA; + else if (!strcmp(buffer, "-----BEGIN EC PRIVATE KEY-----\n")) + ret->type = OSSH_EC; + else { + errmsg = "Unrecognised key type"; + goto error; } - if (ret->keyblob_len == 0 || !ret->keyblob) { - errmsg = "Key body not present"; - goto error; - } + headers_done = 0; + while (1) { + if (!fgets(buffer, sizeof(buffer), fp)) { + errmsg = "Unexpected end of file"; + goto error; + } + if (0 == strncmp(buffer, "-----END ", 9) && + 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) + break; /* done */ + if ((p = strchr(buffer, ':')) != NULL) { + if (headers_done) { + errmsg = "Header found in body of key data"; + goto error; + } + *p++ = '\0'; + while (*p && isspace((unsigned char)*p)) p++; + if (!strcmp(buffer, "Proc-Type")) { + if (p[0] != '4' || p[1] != ',') { + errmsg = "Proc-Type is not 4 (only 4 is supported)"; + goto error; + } + p += 2; + if (!strcmp(p, "ENCRYPTED\n")) + ret->encrypted = 1; + } else if (!strcmp(buffer, "DEK-Info")) { + int i, j; - if (ret->encrypted && ret->keyblob_len % 8 != 0) { - errmsg = "Encrypted key blob is not a multiple of cipher block size"; - goto error; - } + if (strncmp(p, "DES-EDE3-CBC,", 13)) { + errmsg = "Ciphers other than DES-EDE3-CBC not supported"; + goto error; + } + p += 13; + for (i = 0; i < 8; i++) { + if (1 != sscanf(p, "%2x", &j)) + break; + ret->iv[i] = j; + p += 2; + } + if (i < 8) { + errmsg = "Expected 16-digit iv in DEK-Info"; + goto error; + } + } + } else { + headers_done = 1; + len = strlen(buffer); + outlen = len*4/3; + if (ret->keyblob_len + outlen > ret->keyblob_size) { + ret->keyblob_size = ret->keyblob_len + outlen + 256; + ret->keyblob = (unsigned char*)m_realloc(ret->keyblob, + ret->keyblob_size); + } + outlen = ret->keyblob_size - ret->keyblob_len; + if (base64_decode((const unsigned char *)buffer, len, + ret->keyblob + ret->keyblob_len, &outlen) != CRYPT_OK){ + errmsg = "Error decoding base64"; + goto error; + } + ret->keyblob_len += outlen; + } + } + + if (ret->keyblob_len == 0 || !ret->keyblob) { + errmsg = "Key body not present"; + goto error; + } + + if (ret->encrypted && ret->keyblob_len % 8 != 0) { + errmsg = "Encrypted key blob is not a multiple of cipher block size"; + goto error; + } m_burn(buffer, sizeof(buffer)); - return ret; + return ret; - error: +error: m_burn(buffer, sizeof(buffer)); - if (ret) { - if (ret->keyblob) { + if (ret) { + if (ret->keyblob) { m_burn(ret->keyblob, ret->keyblob_size); m_free(ret->keyblob); - } + } m_free(ret); } if (fp) { fclose(fp); - } + } if (errmsg) { fprintf(stderr, "Error: %s\n", errmsg); } - return NULL; + return NULL; } static int openssh_encrypted(const char *filename) { - struct openssh_key *key = load_openssh_key(filename); - int ret; + struct openssh_key *key = load_openssh_key(filename); + int ret; - if (!key) - return 0; - ret = key->encrypted; + if (!key) + return 0; + ret = key->encrypted; m_burn(key->keyblob, key->keyblob_size); m_free(key->keyblob); m_free(key); - return ret; + return ret; } static sign_key *openssh_read(const char *filename, char * UNUSED(passphrase)) { - struct openssh_key *key; - unsigned char *p; - int ret, id, len, flags; - int i, num_integers = 0; - sign_key *retval = NULL; - char *errmsg; - unsigned char *modptr = NULL; - int modlen = -9999; - enum signkey_type type; + struct openssh_key *key; + unsigned char *p; + int ret, id, len, flags; + int i, num_integers = 0; + sign_key *retval = NULL; + char *errmsg; + unsigned char *modptr = NULL; + int modlen = -9999; + enum signkey_type type; - sign_key *retkey; - buffer * blobbuf = NULL; + sign_key *retkey; + buffer * blobbuf = NULL; - retkey = new_sign_key(); + retkey = new_sign_key(); - key = load_openssh_key(filename); + key = load_openssh_key(filename); - if (!key) - return NULL; + if (!key) + return NULL; - if (key->encrypted) { - errmsg = "encrypted keys not supported currently"; - goto error; + if (key->encrypted) { + errmsg = "encrypted keys not supported currently"; + goto error; #if 0 - /* matt TODO */ - /* - * Derive encryption key from passphrase and iv/salt: - * - * - let block A equal MD5(passphrase || iv) - * - let block B equal MD5(A || passphrase || iv) - * - block C would be MD5(B || passphrase || iv) and so on - * - encryption key is the first N bytes of A || B - */ - struct MD5Context md5c; - unsigned char keybuf[32]; + /* matt TODO */ + /* + * Derive encryption key from passphrase and iv/salt: + * + * - let block A equal MD5(passphrase || iv) + * - let block B equal MD5(A || passphrase || iv) + * - block C would be MD5(B || passphrase || iv) and so on + * - encryption key is the first N bytes of A || B + */ + struct MD5Context md5c; + unsigned char keybuf[32]; + + MD5Init(&md5c); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Update(&md5c, (unsigned char *)key->iv, 8); + MD5Final(keybuf, &md5c); - MD5Init(&md5c); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Update(&md5c, (unsigned char *)key->iv, 8); - MD5Final(keybuf, &md5c); + MD5Init(&md5c); + MD5Update(&md5c, keybuf, 16); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Update(&md5c, (unsigned char *)key->iv, 8); + MD5Final(keybuf+16, &md5c); - MD5Init(&md5c); - MD5Update(&md5c, keybuf, 16); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Update(&md5c, (unsigned char *)key->iv, 8); - MD5Final(keybuf+16, &md5c); + /* + * Now decrypt the key blob. + */ + des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv, + key->keyblob, key->keyblob_len); + + memset(&md5c, 0, sizeof(md5c)); + memset(keybuf, 0, sizeof(keybuf)); +#endif + } /* - * Now decrypt the key blob. + * Now we have a decrypted key blob, which contains an ASN.1 + * encoded private key. We must now untangle the ASN.1. + * + * We expect the whole key blob to be formatted as a SEQUENCE + * (0x30 followed by a length code indicating that the rest of + * the blob is part of the sequence). Within that SEQUENCE we + * expect to see a bunch of INTEGERs. What those integers mean + * depends on the key type: + * + * - For RSA, we expect the integers to be 0, n, e, d, p, q, + * dmp1, dmq1, iqmp in that order. (The last three are d mod + * (p-1), d mod (q-1), inverse of q mod p respectively.) + * + * - For DSA, we expect them to be 0, p, q, g, y, x in that + * order. */ - des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv, - key->keyblob, key->keyblob_len); - - memset(&md5c, 0, sizeof(md5c)); - memset(keybuf, 0, sizeof(keybuf)); -#endif - } + + p = key->keyblob; - /* - * Now we have a decrypted key blob, which contains an ASN.1 - * encoded private key. We must now untangle the ASN.1. - * - * We expect the whole key blob to be formatted as a SEQUENCE - * (0x30 followed by a length code indicating that the rest of - * the blob is part of the sequence). Within that SEQUENCE we - * expect to see a bunch of INTEGERs. What those integers mean - * depends on the key type: - * - * - For RSA, we expect the integers to be 0, n, e, d, p, q, - * dmp1, dmq1, iqmp in that order. (The last three are d mod - * (p-1), d mod (q-1), inverse of q mod p respectively.) - * - * - For DSA, we expect them to be 0, p, q, g, y, x in that - * order. - */ - - p = key->keyblob; + /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */ + ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags); + p += ret; + if (ret < 0 || id != 16 || len < 0 || + key->keyblob+key->keyblob_len-p < len) { + errmsg = "ASN.1 decoding failure"; + goto error; + } - /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */ - ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags); - p += ret; - if (ret < 0 || id != 16 || len < 0 || - key->keyblob+key->keyblob_len-p < len) { - errmsg = "ASN.1 decoding failure"; - goto error; - } + /* Expect a load of INTEGERs. */ + if (key->type == OSSH_RSA) + num_integers = 9; + else if (key->type == OSSH_DSA) + num_integers = 6; + else if (key->type == OSSH_EC) + num_integers = 1; - /* Expect a load of INTEGERs. */ - if (key->type == OSSH_RSA) - num_integers = 9; - else if (key->type == OSSH_DSA) - num_integers = 6; - else if (key->type == OSSH_EC) - num_integers = 1; - - /* - * Space to create key blob in. - */ - blobbuf = buf_new(3000); + /* + * Space to create key blob in. + */ + blobbuf = buf_new(3000); #ifdef DROPBEAR_DSS - if (key->type == OSSH_DSA) { - buf_putstring(blobbuf, "ssh-dss", 7); - retkey->type = DROPBEAR_SIGNKEY_DSS; - } + if (key->type == OSSH_DSA) { + buf_putstring(blobbuf, "ssh-dss", 7); + retkey->type = DROPBEAR_SIGNKEY_DSS; + } #endif #ifdef DROPBEAR_RSA - if (key->type == OSSH_RSA) { - buf_putstring(blobbuf, "ssh-rsa", 7); - retkey->type = DROPBEAR_SIGNKEY_RSA; - } + if (key->type == OSSH_RSA) { + buf_putstring(blobbuf, "ssh-rsa", 7); + retkey->type = DROPBEAR_SIGNKEY_RSA; + } #endif - for (i = 0; i < num_integers; i++) { - ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, - &id, &len, &flags); - p += ret; - if (ret < 0 || id != 2 || len < 0 || - key->keyblob+key->keyblob_len-p < len) { - errmsg = "ASN.1 decoding failure"; - goto error; - } - - if (i == 0) { - /* First integer is a version indicator */ - int expected = -1; - switch (key->type) { - case OSSH_RSA: - case OSSH_DSA: - expected = 0; - break; - case OSSH_EC: - expected = 1; - break; - } - if (len != 1 || p[0] != expected) { - errmsg = "Version number mismatch"; - goto error; - } - } else if (key->type == OSSH_RSA) { - /* - * OpenSSH key order is n, e, d, p, q, dmp1, dmq1, iqmp - * but we want e, n, d, p, q - */ - if (i == 1) { - /* Save the details for after we deal with number 2. */ - modptr = p; - modlen = len; - } else if (i >= 2 && i <= 5) { - buf_putstring(blobbuf, (const char*)p, len); - if (i == 2) { - buf_putstring(blobbuf, (const char*)modptr, modlen); - } - } - } else if (key->type == OSSH_DSA) { - /* - * OpenSSH key order is p, q, g, y, x, - * we want the same. - */ - buf_putstring(blobbuf, (const char*)p, len); - } - - /* Skip past the number. */ - p += len; - } - -#ifdef DROPBEAR_ECDSA - if (key->type == OSSH_EC) { - unsigned char* private_key_bytes = NULL; - int private_key_len = 0; - unsigned char* public_key_bytes = NULL; - int public_key_len = 0; - ecc_key *ecc = NULL; - const struct dropbear_ecc_curve *curve = NULL; - - /* See SEC1 v2, Appendix C.4 */ - /* OpenSSL (so OpenSSH) seems to include the optional parts. */ - - /* privateKey OCTET STRING, */ + for (i = 0; i < num_integers; i++) { ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, &id, &len, &flags); p += ret; - /* id==4 for octet string */ - if (ret < 0 || id != 4 || len < 0 || - key->keyblob+key->keyblob_len-p < len) { - errmsg = "ASN.1 decoding failure"; - goto error; - } - private_key_bytes = p; - private_key_len = len; - p += len; - - /* parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, */ - ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, - &id, &len, &flags); - p += ret; - /* id==0 */ - if (ret < 0 || id != 0 || len < 0) { - errmsg = "ASN.1 decoding failure"; - goto error; - } - - ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, - &id, &len, &flags); - p += ret; - /* id==6 for object */ - if (ret < 0 || id != 6 || len < 0 || + if (ret < 0 || id != 2 || len < 0 || key->keyblob+key->keyblob_len-p < len) { errmsg = "ASN.1 decoding failure"; goto error; } - if (0) {} -#ifdef DROPBEAR_ECC_256 - else if (len == sizeof(OID_SEC256R1_BLOB) - && memcmp(p, OID_SEC256R1_BLOB, len) == 0) { - retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP256; - curve = &ecc_curve_nistp256; - } -#endif -#ifdef DROPBEAR_ECC_384 - else if (len == sizeof(OID_SEC384R1_BLOB) - && memcmp(p, OID_SEC384R1_BLOB, len) == 0) { - retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP384; - curve = &ecc_curve_nistp384; - } -#endif -#ifdef DROPBEAR_ECC_521 - else if (len == sizeof(OID_SEC521R1_BLOB) - && memcmp(p, OID_SEC521R1_BLOB, len) == 0) { - retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP521; - curve = &ecc_curve_nistp521; - } -#endif - else { - errmsg = "Unknown ECC key type"; - goto error; - } - p += len; - - /* publicKey [1] BIT STRING OPTIONAL */ - ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, - &id, &len, &flags); - p += ret; - /* id==1 */ - if (ret < 0 || id != 1 || len < 0) { - errmsg = "ASN.1 decoding failure"; - goto error; + if (i == 0) { + /* First integer is a version indicator */ + int expected = -1; + switch (key->type) { + case OSSH_RSA: + case OSSH_DSA: + expected = 0; + break; + case OSSH_EC: + expected = 1; + break; + } + if (len != 1 || p[0] != expected) { + errmsg = "Version number mismatch"; + goto error; + } + } else if (key->type == OSSH_RSA) { + /* + * OpenSSH key order is n, e, d, p, q, dmp1, dmq1, iqmp + * but we want e, n, d, p, q + */ + if (i == 1) { + /* Save the details for after we deal with number 2. */ + modptr = p; + modlen = len; + } else if (i >= 2 && i <= 5) { + buf_putstring(blobbuf, (const char*)p, len); + if (i == 2) { + buf_putstring(blobbuf, (const char*)modptr, modlen); + } + } + } else if (key->type == OSSH_DSA) { + /* + * OpenSSH key order is p, q, g, y, x, + * we want the same. + */ + buf_putstring(blobbuf, (const char*)p, len); } - ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, - &id, &len, &flags); - p += ret; - /* id==3 for bit string */ - if (ret < 0 || id != 3 || len < 0 || - key->keyblob+key->keyblob_len-p < len) { - errmsg = "ASN.1 decoding failure"; - goto error; - } - public_key_bytes = p+1; - public_key_len = len-1; + /* Skip past the number. */ p += len; + } - buf_putbytes(blobbuf, public_key_bytes, public_key_len); - ecc = buf_get_ecc_raw_pubkey(blobbuf, curve); - if (!ecc) { - errmsg = "Error parsing ECC key"; - goto error; +#ifdef DROPBEAR_ECDSA + if (key->type == OSSH_EC) { + unsigned char* private_key_bytes = NULL; + int private_key_len = 0; + unsigned char* public_key_bytes = NULL; + int public_key_len = 0; + ecc_key *ecc = NULL; + const struct dropbear_ecc_curve *curve = NULL; + + /* See SEC1 v2, Appendix C.4 */ + /* OpenSSL (so OpenSSH) seems to include the optional parts. */ + + /* privateKey OCTET STRING, */ + ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, + &id, &len, &flags); + p += ret; + /* id==4 for octet string */ + if (ret < 0 || id != 4 || len < 0 || + key->keyblob+key->keyblob_len-p < len) { + errmsg = "ASN.1 decoding failure"; + goto error; + } + private_key_bytes = p; + private_key_len = len; + p += len; + + /* parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, */ + ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, + &id, &len, &flags); + p += ret; + /* id==0 */ + if (ret < 0 || id != 0 || len < 0) { + errmsg = "ASN.1 decoding failure"; + goto error; + } + + ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, + &id, &len, &flags); + p += ret; + /* id==6 for object */ + if (ret < 0 || id != 6 || len < 0 || + key->keyblob+key->keyblob_len-p < len) { + errmsg = "ASN.1 decoding failure"; + goto error; + } + + if (0) {} +#ifdef DROPBEAR_ECC_256 + else if (len == sizeof(OID_SEC256R1_BLOB) + && memcmp(p, OID_SEC256R1_BLOB, len) == 0) { + retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP256; + curve = &ecc_curve_nistp256; + } +#endif +#ifdef DROPBEAR_ECC_384 + else if (len == sizeof(OID_SEC384R1_BLOB) + && memcmp(p, OID_SEC384R1_BLOB, len) == 0) { + retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP384; + curve = &ecc_curve_nistp384; + } +#endif +#ifdef DROPBEAR_ECC_521 + else if (len == sizeof(OID_SEC521R1_BLOB) + && memcmp(p, OID_SEC521R1_BLOB, len) == 0) { + retkey->type = DROPBEAR_SIGNKEY_ECDSA_NISTP521; + curve = &ecc_curve_nistp521; + } +#endif + else { + errmsg = "Unknown ECC key type"; + goto error; + } + p += len; + + /* publicKey [1] BIT STRING OPTIONAL */ + ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, + &id, &len, &flags); + p += ret; + /* id==1 */ + if (ret < 0 || id != 1 || len < 0) { + errmsg = "ASN.1 decoding failure"; + goto error; + } + + ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p, + &id, &len, &flags); + p += ret; + /* id==3 for bit string */ + if (ret < 0 || id != 3 || len < 0 || + key->keyblob+key->keyblob_len-p < len) { + errmsg = "ASN.1 decoding failure"; + goto error; + } + public_key_bytes = p+1; + public_key_len = len-1; + p += len; + + buf_putbytes(blobbuf, public_key_bytes, public_key_len); + ecc = buf_get_ecc_raw_pubkey(blobbuf, curve); + if (!ecc) { + errmsg = "Error parsing ECC key"; + goto error; + } + m_mp_alloc_init_multi((mp_int**)&ecc->k, NULL); + if (mp_read_unsigned_bin(ecc->k, private_key_bytes, private_key_len) + != MP_OKAY) { + errmsg = "Error parsing ECC key"; + goto error; + } + + *signkey_key_ptr(retkey, retkey->type) = ecc; } - m_mp_alloc_init_multi((mp_int**)&ecc->k, NULL); - if (mp_read_unsigned_bin(ecc->k, private_key_bytes, private_key_len) - != MP_OKAY) { - errmsg = "Error parsing ECC key"; - goto error; +#endif /* DROPBEAR_ECDSA */ + + /* + * Now put together the actual key. Simplest way to do this is + * to assemble our own key blobs and feed them to the createkey + * functions; this is a bit faffy but it does mean we get all + * the sanity checks for free. + */ + if (key->type == OSSH_RSA || key->type == OSSH_DSA) { + buf_setpos(blobbuf, 0); + type = DROPBEAR_SIGNKEY_ANY; + if (buf_get_priv_key(blobbuf, retkey, &type) + != DROPBEAR_SUCCESS) { + errmsg = "unable to create key structure"; + sign_key_free(retkey); + retkey = NULL; + goto error; + } } - *signkey_key_ptr(retkey, retkey->type) = ecc; - } -#endif /* DROPBEAR_ECDSA */ + errmsg = NULL; /* no error */ + retval = retkey; - /* - * Now put together the actual key. Simplest way to do this is - * to assemble our own key blobs and feed them to the createkey - * functions; this is a bit faffy but it does mean we get all - * the sanity checks for free. - */ - if (key->type == OSSH_RSA || key->type == OSSH_DSA) { - buf_setpos(blobbuf, 0); - type = DROPBEAR_SIGNKEY_ANY; - if (buf_get_priv_key(blobbuf, retkey, &type) - != DROPBEAR_SUCCESS) { - errmsg = "unable to create key structure"; - sign_key_free(retkey); - retkey = NULL; - goto error; - } - } - - errmsg = NULL; /* no error */ - retval = retkey; - - error: + error: if (blobbuf) { buf_burn(blobbuf); buf_free(blobbuf); - } + } m_burn(key->keyblob, key->keyblob_size); m_free(key->keyblob); m_burn(key, sizeof(*key)); @@ -822,372 +822,372 @@ if (errmsg) { fprintf(stderr, "Error: %s\n", errmsg); } - return retval; + return retval; } static int openssh_write(const char *filename, sign_key *key, - char *passphrase) + char *passphrase) { - buffer * keyblob = NULL; - buffer * extrablob = NULL; /* used for calculated values to write */ - unsigned char *outblob = NULL; - int outlen = -9999; - struct mpint_pos numbers[9]; - int nnumbers = -1, pos = 0, len = 0, seqlen, i; - char *header = NULL, *footer = NULL; - char zero[1]; - int ret = 0; - FILE *fp; + buffer * keyblob = NULL; + buffer * extrablob = NULL; /* used for calculated values to write */ + unsigned char *outblob = NULL; + int outlen = -9999; + struct mpint_pos numbers[9]; + int nnumbers = -1, pos = 0, len = 0, seqlen, i; + char *header = NULL, *footer = NULL; + char zero[1]; + int ret = 0; + FILE *fp; #ifdef DROPBEAR_RSA - mp_int dmp1, dmq1, iqmp, tmpval; /* for rsa */ + mp_int dmp1, dmq1, iqmp, tmpval; /* for rsa */ #endif - if ( + if ( #ifdef DROPBEAR_RSA - key->type == DROPBEAR_SIGNKEY_RSA || + key->type == DROPBEAR_SIGNKEY_RSA || #endif #ifdef DROPBEAR_DSS - key->type == DROPBEAR_SIGNKEY_DSS || + key->type == DROPBEAR_SIGNKEY_DSS || #endif - 0) - { - /* - * Fetch the key blobs. - */ - keyblob = buf_new(3000); - buf_put_priv_key(keyblob, key, key->type); + 0) + { + /* + * Fetch the key blobs. + */ + keyblob = buf_new(3000); + buf_put_priv_key(keyblob, key, key->type); - buf_setpos(keyblob, 0); - /* skip the "ssh-rsa" or "ssh-dss" header */ - buf_incrpos(keyblob, buf_getint(keyblob)); + buf_setpos(keyblob, 0); + /* skip the "ssh-rsa" or "ssh-dss" header */ + buf_incrpos(keyblob, buf_getint(keyblob)); - /* - * Find the sequence of integers to be encoded into the OpenSSH - * key blob, and also decide on the header line. - */ - numbers[0].start = zero; numbers[0].bytes = 1; zero[0] = '\0'; + /* + * Find the sequence of integers to be encoded into the OpenSSH + * key blob, and also decide on the header line. + */ + numbers[0].start = zero; numbers[0].bytes = 1; zero[0] = '\0'; - #ifdef DROPBEAR_RSA - if (key->type == DROPBEAR_SIGNKEY_RSA) { + #ifdef DROPBEAR_RSA + if (key->type == DROPBEAR_SIGNKEY_RSA) { - if (key->rsakey->p == NULL || key->rsakey->q == NULL) { - fprintf(stderr, "Pre-0.33 Dropbear keys cannot be converted to OpenSSH keys.\n"); - goto error; - } + if (key->rsakey->p == NULL || key->rsakey->q == NULL) { + fprintf(stderr, "Pre-0.33 Dropbear keys cannot be converted to OpenSSH keys.\n"); + goto error; + } - /* e */ - numbers[2].bytes = buf_getint(keyblob); - numbers[2].start = buf_getptr(keyblob, numbers[2].bytes); - buf_incrpos(keyblob, numbers[2].bytes); + /* e */ + numbers[2].bytes = buf_getint(keyblob); + numbers[2].start = buf_getptr(keyblob, numbers[2].bytes); + buf_incrpos(keyblob, numbers[2].bytes); - /* n */ - numbers[1].bytes = buf_getint(keyblob); - numbers[1].start = buf_getptr(keyblob, numbers[1].bytes); - buf_incrpos(keyblob, numbers[1].bytes); + /* n */ + numbers[1].bytes = buf_getint(keyblob); + numbers[1].start = buf_getptr(keyblob, numbers[1].bytes); + buf_incrpos(keyblob, numbers[1].bytes); - /* d */ - numbers[3].bytes = buf_getint(keyblob); - numbers[3].start = buf_getptr(keyblob, numbers[3].bytes); - buf_incrpos(keyblob, numbers[3].bytes); + /* d */ + numbers[3].bytes = buf_getint(keyblob); + numbers[3].start = buf_getptr(keyblob, numbers[3].bytes); + buf_incrpos(keyblob, numbers[3].bytes); - /* p */ - numbers[4].bytes = buf_getint(keyblob); - numbers[4].start = buf_getptr(keyblob, numbers[4].bytes); - buf_incrpos(keyblob, numbers[4].bytes); - - /* q */ - numbers[5].bytes = buf_getint(keyblob); - numbers[5].start = buf_getptr(keyblob, numbers[5].bytes); - buf_incrpos(keyblob, numbers[5].bytes); + /* p */ + numbers[4].bytes = buf_getint(keyblob); + numbers[4].start = buf_getptr(keyblob, numbers[4].bytes); + buf_incrpos(keyblob, numbers[4].bytes); + + /* q */ + numbers[5].bytes = buf_getint(keyblob); + numbers[5].start = buf_getptr(keyblob, numbers[5].bytes); + buf_incrpos(keyblob, numbers[5].bytes); - /* now calculate some extra parameters: */ - m_mp_init(&tmpval); - m_mp_init(&dmp1); - m_mp_init(&dmq1); - m_mp_init(&iqmp); + /* now calculate some extra parameters: */ + m_mp_init(&tmpval); + m_mp_init(&dmp1); + m_mp_init(&dmq1); + m_mp_init(&iqmp); - /* dmp1 = d mod (p-1) */ - if (mp_sub_d(key->rsakey->p, 1, &tmpval) != MP_OKAY) { - fprintf(stderr, "Bignum error for p-1\n"); - goto error; - } - if (mp_mod(key->rsakey->d, &tmpval, &dmp1) != MP_OKAY) { - fprintf(stderr, "Bignum error for dmp1\n"); - goto error; - } + /* dmp1 = d mod (p-1) */ + if (mp_sub_d(key->rsakey->p, 1, &tmpval) != MP_OKAY) { + fprintf(stderr, "Bignum error for p-1\n"); + goto error; + } + if (mp_mod(key->rsakey->d, &tmpval, &dmp1) != MP_OKAY) { + fprintf(stderr, "Bignum error for dmp1\n"); + goto error; + } - /* dmq1 = d mod (q-1) */ - if (mp_sub_d(key->rsakey->q, 1, &tmpval) != MP_OKAY) { - fprintf(stderr, "Bignum error for q-1\n"); - goto error; - } - if (mp_mod(key->rsakey->d, &tmpval, &dmq1) != MP_OKAY) { - fprintf(stderr, "Bignum error for dmq1\n"); - goto error; - } + /* dmq1 = d mod (q-1) */ + if (mp_sub_d(key->rsakey->q, 1, &tmpval) != MP_OKAY) { + fprintf(stderr, "Bignum error for q-1\n"); + goto error; + } + if (mp_mod(key->rsakey->d, &tmpval, &dmq1) != MP_OKAY) { + fprintf(stderr, "Bignum error for dmq1\n"); + goto error; + } - /* iqmp = (q^-1) mod p */ - if (mp_invmod(key->rsakey->q, key->rsakey->p, &iqmp) != MP_OKAY) { - fprintf(stderr, "Bignum error for iqmp\n"); - goto error; - } + /* iqmp = (q^-1) mod p */ + if (mp_invmod(key->rsakey->q, key->rsakey->p, &iqmp) != MP_OKAY) { + fprintf(stderr, "Bignum error for iqmp\n"); + goto error; + } - extrablob = buf_new(2000); - buf_putmpint(extrablob, &dmp1); - buf_putmpint(extrablob, &dmq1); - buf_putmpint(extrablob, &iqmp); - buf_setpos(extrablob, 0); - mp_clear(&dmp1); - mp_clear(&dmq1); - mp_clear(&iqmp); - mp_clear(&tmpval); - - /* dmp1 */ - numbers[6].bytes = buf_getint(extrablob); - numbers[6].start = buf_getptr(extrablob, numbers[6].bytes); - buf_incrpos(extrablob, numbers[6].bytes); - - /* dmq1 */ - numbers[7].bytes = buf_getint(extrablob); - numbers[7].start = buf_getptr(extrablob, numbers[7].bytes); - buf_incrpos(extrablob, numbers[7].bytes); - - /* iqmp */ - numbers[8].bytes = buf_getint(extrablob); - numbers[8].start = buf_getptr(extrablob, numbers[8].bytes); - buf_incrpos(extrablob, numbers[8].bytes); + extrablob = buf_new(2000); + buf_putmpint(extrablob, &dmp1); + buf_putmpint(extrablob, &dmq1); + buf_putmpint(extrablob, &iqmp); + buf_setpos(extrablob, 0); + mp_clear(&dmp1); + mp_clear(&dmq1); + mp_clear(&iqmp); + mp_clear(&tmpval); + + /* dmp1 */ + numbers[6].bytes = buf_getint(extrablob); + numbers[6].start = buf_getptr(extrablob, numbers[6].bytes); + buf_incrpos(extrablob, numbers[6].bytes); + + /* dmq1 */ + numbers[7].bytes = buf_getint(extrablob); + numbers[7].start = buf_getptr(extrablob, numbers[7].bytes); + buf_incrpos(extrablob, numbers[7].bytes); + + /* iqmp */ + numbers[8].bytes = buf_getint(extrablob); + numbers[8].start = buf_getptr(extrablob, numbers[8].bytes); + buf_incrpos(extrablob, numbers[8].bytes); - nnumbers = 9; - header = "-----BEGIN RSA PRIVATE KEY-----\n"; - footer = "-----END RSA PRIVATE KEY-----\n"; - } - #endif /* DROPBEAR_RSA */ + nnumbers = 9; + header = "-----BEGIN RSA PRIVATE KEY-----\n"; + footer = "-----END RSA PRIVATE KEY-----\n"; + } + #endif /* DROPBEAR_RSA */ - #ifdef DROPBEAR_DSS - if (key->type == DROPBEAR_SIGNKEY_DSS) { + #ifdef DROPBEAR_DSS + if (key->type == DROPBEAR_SIGNKEY_DSS) { - /* p */ - numbers[1].bytes = buf_getint(keyblob); - numbers[1].start = buf_getptr(keyblob, numbers[1].bytes); - buf_incrpos(keyblob, numbers[1].bytes); + /* p */ + numbers[1].bytes = buf_getint(keyblob); + numbers[1].start = buf_getptr(keyblob, numbers[1].bytes); + buf_incrpos(keyblob, numbers[1].bytes); - /* q */ - numbers[2].bytes = buf_getint(keyblob); - numbers[2].start = buf_getptr(keyblob, numbers[2].bytes); - buf_incrpos(keyblob, numbers[2].bytes); + /* q */ + numbers[2].bytes = buf_getint(keyblob); + numbers[2].start = buf_getptr(keyblob, numbers[2].bytes); + buf_incrpos(keyblob, numbers[2].bytes); - /* g */ - numbers[3].bytes = buf_getint(keyblob); - numbers[3].start = buf_getptr(keyblob, numbers[3].bytes); - buf_incrpos(keyblob, numbers[3].bytes); + /* g */ + numbers[3].bytes = buf_getint(keyblob); + numbers[3].start = buf_getptr(keyblob, numbers[3].bytes); + buf_incrpos(keyblob, numbers[3].bytes); - /* y */ - numbers[4].bytes = buf_getint(keyblob); - numbers[4].start = buf_getptr(keyblob, numbers[4].bytes); - buf_incrpos(keyblob, numbers[4].bytes); + /* y */ + numbers[4].bytes = buf_getint(keyblob); + numbers[4].start = buf_getptr(keyblob, numbers[4].bytes); + buf_incrpos(keyblob, numbers[4].bytes); - /* x */ - numbers[5].bytes = buf_getint(keyblob); - numbers[5].start = buf_getptr(keyblob, numbers[5].bytes); - buf_incrpos(keyblob, numbers[5].bytes); + /* x */ + numbers[5].bytes = buf_getint(keyblob); + numbers[5].start = buf_getptr(keyblob, numbers[5].bytes); + buf_incrpos(keyblob, numbers[5].bytes); - nnumbers = 6; - header = "-----BEGIN DSA PRIVATE KEY-----\n"; - footer = "-----END DSA PRIVATE KEY-----\n"; - } - #endif /* DROPBEAR_DSS */ + nnumbers = 6; + header = "-----BEGIN DSA PRIVATE KEY-----\n"; + footer = "-----END DSA PRIVATE KEY-----\n"; + } + #endif /* DROPBEAR_DSS */ - /* - * Now count up the total size of the ASN.1 encoded integers, - * so as to determine the length of the containing SEQUENCE. - */ - len = 0; - for (i = 0; i < nnumbers; i++) { - len += ber_write_id_len(NULL, 2, numbers[i].bytes, 0); - len += numbers[i].bytes; - } - seqlen = len; - /* Now add on the SEQUENCE header. */ - len += ber_write_id_len(NULL, 16, seqlen, ASN1_CONSTRUCTED); - /* Round up to the cipher block size, ensuring we have at least one - * byte of padding (see below). */ - outlen = len; - if (passphrase) - outlen = (outlen+8) &~ 7; + /* + * Now count up the total size of the ASN.1 encoded integers, + * so as to determine the length of the containing SEQUENCE. + */ + len = 0; + for (i = 0; i < nnumbers; i++) { + len += ber_write_id_len(NULL, 2, numbers[i].bytes, 0); + len += numbers[i].bytes; + } + seqlen = len; + /* Now add on the SEQUENCE header. */ + len += ber_write_id_len(NULL, 16, seqlen, ASN1_CONSTRUCTED); + /* Round up to the cipher block size, ensuring we have at least one + * byte of padding (see below). */ + outlen = len; + if (passphrase) + outlen = (outlen+8) &~ 7; - /* - * Now we know how big outblob needs to be. Allocate it. - */ - outblob = (unsigned char*)m_malloc(outlen); + /* + * Now we know how big outblob needs to be. Allocate it. + */ + outblob = (unsigned char*)m_malloc(outlen); - /* - * And write the data into it. - */ - pos = 0; - pos += ber_write_id_len(outblob+pos, 16, seqlen, ASN1_CONSTRUCTED); - for (i = 0; i < nnumbers; i++) { - pos += ber_write_id_len(outblob+pos, 2, numbers[i].bytes, 0); - memcpy(outblob+pos, numbers[i].start, numbers[i].bytes); - pos += numbers[i].bytes; - } - } /* end RSA and DSS handling */ + /* + * And write the data into it. + */ + pos = 0; + pos += ber_write_id_len(outblob+pos, 16, seqlen, ASN1_CONSTRUCTED); + for (i = 0; i < nnumbers; i++) { + pos += ber_write_id_len(outblob+pos, 2, numbers[i].bytes, 0); + memcpy(outblob+pos, numbers[i].start, numbers[i].bytes); + pos += numbers[i].bytes; + } + } /* end RSA and DSS handling */ #ifdef DROPBEAR_ECDSA - if (key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP256 - || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP384 - || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP521) { + if (key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP256 + || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP384 + || key->type == DROPBEAR_SIGNKEY_ECDSA_NISTP521) { - /* SEC1 V2 appendix c.4 - ECPrivateKey ::= SEQUENCE { - version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), - privateKey OCTET STRING, - parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, - publicKey [1] BIT STRING OPTIONAL - } - */ - buffer *seq_buf = buf_new(400); - ecc_key **eck = (ecc_key**)signkey_key_ptr(key, key->type); - const long curve_size = (*eck)->dp->size; - int curve_oid_len = 0; - const void* curve_oid = NULL; - unsigned long pubkey_size = 2*curve_size+1; - int k_size; - int err = 0; + /* SEC1 V2 appendix c.4 + ECPrivateKey ::= SEQUENCE { + version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), + privateKey OCTET STRING, + parameters [0] ECDomainParameters {{ SECGCurveNames }} OPTIONAL, + publicKey [1] BIT STRING OPTIONAL + } + */ + buffer *seq_buf = buf_new(400); + ecc_key **eck = (ecc_key**)signkey_key_ptr(key, key->type); + const long curve_size = (*eck)->dp->size; + int curve_oid_len = 0; + const void* curve_oid = NULL; + unsigned long pubkey_size = 2*curve_size+1; + int k_size; + int err = 0; - /* version. less than 10 bytes */ - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 2, 1, 0)); - buf_putbyte(seq_buf, 1); + /* version. less than 10 bytes */ + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 2, 1, 0)); + buf_putbyte(seq_buf, 1); - /* privateKey */ - k_size = mp_unsigned_bin_size((*eck)->k); - dropbear_assert(k_size <= curve_size); - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 4, k_size, 0)); - mp_to_unsigned_bin((*eck)->k, buf_getwriteptr(seq_buf, k_size)); - buf_incrwritepos(seq_buf, k_size); + /* privateKey */ + k_size = mp_unsigned_bin_size((*eck)->k); + dropbear_assert(k_size <= curve_size); + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 4, k_size, 0)); + mp_to_unsigned_bin((*eck)->k, buf_getwriteptr(seq_buf, k_size)); + buf_incrwritepos(seq_buf, k_size); - /* SECGCurveNames */ - switch (key->type) - { - case DROPBEAR_SIGNKEY_ECDSA_NISTP256: - curve_oid_len = sizeof(OID_SEC256R1_BLOB); - curve_oid = OID_SEC256R1_BLOB; - break; - case DROPBEAR_SIGNKEY_ECDSA_NISTP384: - curve_oid_len = sizeof(OID_SEC384R1_BLOB); - curve_oid = OID_SEC384R1_BLOB; - break; - case DROPBEAR_SIGNKEY_ECDSA_NISTP521: - curve_oid_len = sizeof(OID_SEC521R1_BLOB); - curve_oid = OID_SEC521R1_BLOB; - break; - default: - dropbear_exit("Internal error"); - } + /* SECGCurveNames */ + switch (key->type) + { + case DROPBEAR_SIGNKEY_ECDSA_NISTP256: + curve_oid_len = sizeof(OID_SEC256R1_BLOB); + curve_oid = OID_SEC256R1_BLOB; + break; + case DROPBEAR_SIGNKEY_ECDSA_NISTP384: + curve_oid_len = sizeof(OID_SEC384R1_BLOB); + curve_oid = OID_SEC384R1_BLOB; + break; + case DROPBEAR_SIGNKEY_ECDSA_NISTP521: + curve_oid_len = sizeof(OID_SEC521R1_BLOB); + curve_oid = OID_SEC521R1_BLOB; + break; + default: + dropbear_exit("Internal error"); + } - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 0, 2+curve_oid_len, 0xa0)); - /* object == 6 */ - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 6, curve_oid_len, 0)); - buf_putbytes(seq_buf, curve_oid, curve_oid_len); + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 0, 2+curve_oid_len, 0xa0)); + /* object == 6 */ + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 6, curve_oid_len, 0)); + buf_putbytes(seq_buf, curve_oid, curve_oid_len); - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 1, 2+1+pubkey_size, 0xa0)); - buf_incrwritepos(seq_buf, - ber_write_id_len(buf_getwriteptr(seq_buf, 10), 3, 1+pubkey_size, 0)); - buf_putbyte(seq_buf, 0); - err = ecc_ansi_x963_export(*eck, buf_getwriteptr(seq_buf, pubkey_size), &pubkey_size); - if (err != CRYPT_OK) { - dropbear_exit("ECC error"); - } - buf_incrwritepos(seq_buf, pubkey_size); + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 1, 2+1+pubkey_size, 0xa0)); + buf_incrwritepos(seq_buf, + ber_write_id_len(buf_getwriteptr(seq_buf, 10), 3, 1+pubkey_size, 0)); + buf_putbyte(seq_buf, 0); + err = ecc_ansi_x963_export(*eck, buf_getwriteptr(seq_buf, pubkey_size), &pubkey_size); + if (err != CRYPT_OK) { + dropbear_exit("ECC error"); + } + buf_incrwritepos(seq_buf, pubkey_size); - buf_setpos(seq_buf, 0); - - outblob = (unsigned char*)m_malloc(1000); + buf_setpos(seq_buf, 0); + + outblob = (unsigned char*)m_malloc(1000); - pos = 0; - pos += ber_write_id_len(outblob+pos, 16, seq_buf->len, ASN1_CONSTRUCTED); - memcpy(&outblob[pos], seq_buf->data, seq_buf->len); - pos += seq_buf->len; - len = pos; - outlen = len; + pos = 0; + pos += ber_write_id_len(outblob+pos, 16, seq_buf->len, ASN1_CONSTRUCTED); + memcpy(&outblob[pos], seq_buf->data, seq_buf->len); + pos += seq_buf->len; + len = pos; + outlen = len; - buf_burn(seq_buf); - buf_free(seq_buf); - seq_buf = NULL; + buf_burn(seq_buf); + buf_free(seq_buf); + seq_buf = NULL; - header = "-----BEGIN EC PRIVATE KEY-----\n"; - footer = "-----END EC PRIVATE KEY-----\n"; - } + header = "-----BEGIN EC PRIVATE KEY-----\n"; + footer = "-----END EC PRIVATE KEY-----\n"; + } #endif - /* - * Padding on OpenSSH keys is deterministic. The number of - * padding bytes is always more than zero, and always at most - * the cipher block length. The value of each padding byte is - * equal to the number of padding bytes. So a plaintext that's - * an exact multiple of the block size will be padded with 08 - * 08 08 08 08 08 08 08 (assuming a 64-bit block cipher); a - * plaintext one byte less than a multiple of the block size - * will be padded with just 01. - * - * This enables the OpenSSL key decryption function to strip - * off the padding algorithmically and return the unpadded - * plaintext to the next layer: it looks at the final byte, and - * then expects to find that many bytes at the end of the data - * with the same value. Those are all removed and the rest is - * returned. - */ - dropbear_assert(pos == len); - while (pos < outlen) { - outblob[pos++] = outlen - len; - } + /* + * Padding on OpenSSH keys is deterministic. The number of + * padding bytes is always more than zero, and always at most + * the cipher block length. The value of each padding byte is + * equal to the number of padding bytes. So a plaintext that's + * an exact multiple of the block size will be padded with 08 + * 08 08 08 08 08 08 08 (assuming a 64-bit block cipher); a + * plaintext one byte less than a multiple of the block size + * will be padded with just 01. + * + * This enables the OpenSSL key decryption function to strip + * off the padding algorithmically and return the unpadded + * plaintext to the next layer: it looks at the final byte, and + * then expects to find that many bytes at the end of the data + * with the same value. Those are all removed and the rest is + * returned. + */ + dropbear_assert(pos == len); + while (pos < outlen) { + outblob[pos++] = outlen - len; + } - /* - * Encrypt the key. - */ - if (passphrase) { - fprintf(stderr, "Encrypted keys aren't supported currently\n"); - goto error; - } + /* + * Encrypt the key. + */ + if (passphrase) { + fprintf(stderr, "Encrypted keys aren't supported currently\n"); + goto error; + } - /* - * And save it. We'll use Unix line endings just in case it's - * subsequently transferred in binary mode. - */ - if (strlen(filename) == 1 && filename[0] == '-') { - fp = stdout; - } else { - fp = fopen(filename, "wb"); /* ensure Unix line endings */ + /* + * And save it. We'll use Unix line endings just in case it's + * subsequently transferred in binary mode. + */ + if (strlen(filename) == 1 && filename[0] == '-') { + fp = stdout; + } else { + fp = fopen(filename, "wb"); /* ensure Unix line endings */ + } + if (!fp) { + fprintf(stderr, "Failed opening output file\n"); + goto error; + } + fputs(header, fp); + base64_encode_fp(fp, outblob, outlen, 64); + fputs(footer, fp); + fclose(fp); + ret = 1; + + error: + if (outblob) { + memset(outblob, 0, outlen); + m_free(outblob); } - if (!fp) { - fprintf(stderr, "Failed opening output file\n"); - goto error; - } - fputs(header, fp); - base64_encode_fp(fp, outblob, outlen, 64); - fputs(footer, fp); - fclose(fp); - ret = 1; - - error: - if (outblob) { - memset(outblob, 0, outlen); - m_free(outblob); - } if (keyblob) { buf_burn(keyblob); buf_free(keyblob); - } + } if (extrablob) { buf_burn(extrablob); buf_free(extrablob); - } - return ret; + } + return ret; } #if 0 @@ -1270,673 +1270,673 @@ #define SSHCOM_MAGIC_NUMBER 0x3f6ff9eb struct sshcom_key { - char comment[256]; /* allowing any length is overkill */ - unsigned char *keyblob; - int keyblob_len, keyblob_size; + char comment[256]; /* allowing any length is overkill */ + unsigned char *keyblob; + int keyblob_len, keyblob_size; }; static struct sshcom_key *load_sshcom_key(const char *filename) { - struct sshcom_key *ret; - FILE *fp; - char buffer[256]; - int len; - char *errmsg, *p; - int headers_done; - char base64_bit[4]; - int base64_chars = 0; - - ret = snew(struct sshcom_key); - ret->comment[0] = '\0'; - ret->keyblob = NULL; - ret->keyblob_len = ret->keyblob_size = 0; + struct sshcom_key *ret; + FILE *fp; + char buffer[256]; + int len; + char *errmsg, *p; + int headers_done; + char base64_bit[4]; + int base64_chars = 0; - fp = fopen(filename, "r"); - if (!fp) { - errmsg = "Unable to open key file"; - goto error; - } - if (!fgets(buffer, sizeof(buffer), fp) || - 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) { - errmsg = "File does not begin with ssh.com key header"; - goto error; - } + ret = snew(struct sshcom_key); + ret->comment[0] = '\0'; + ret->keyblob = NULL; + ret->keyblob_len = ret->keyblob_size = 0; - headers_done = 0; - while (1) { - if (!fgets(buffer, sizeof(buffer), fp)) { - errmsg = "Unexpected end of file"; - goto error; + fp = fopen(filename, "r"); + if (!fp) { + errmsg = "Unable to open key file"; + goto error; } - if (!strcmp(buffer, "---- END SSH2 ENCRYPTED PRIVATE KEY ----\n")) - break; /* done */ - if ((p = strchr(buffer, ':')) != NULL) { - if (headers_done) { - errmsg = "Header found in body of key data"; + if (!fgets(buffer, sizeof(buffer), fp) || + 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) { + errmsg = "File does not begin with ssh.com key header"; goto error; - } - *p++ = '\0'; - while (*p && isspace((unsigned char)*p)) p++; - /* - * Header lines can end in a trailing backslash for - * continuation. - */ - while ((len = strlen(p)) > (int)(sizeof(buffer) - (p-buffer) -1) || - p[len-1] != '\n' || p[len-2] == '\\') { - if (len > (int)((p-buffer) + sizeof(buffer)-2)) { - errmsg = "Header line too long to deal with"; - goto error; - } - if (!fgets(p+len-2, sizeof(buffer)-(p-buffer)-(len-2), fp)) { - errmsg = "Unexpected end of file"; - goto error; - } - } - p[strcspn(p, "\n")] = '\0'; - if (!strcmp(buffer, "Comment")) { - /* Strip quotes in comment if present. */ - if (p[0] == '"' && p[strlen(p)-1] == '"') { - p++; - p[strlen(p)-1] = '\0'; - } - strncpy(ret->comment, p, sizeof(ret->comment)); - ret->comment[sizeof(ret->comment)-1] = '\0'; - } - } else { - headers_done = 1; + } - p = buffer; - while (isbase64(*p)) { - base64_bit[base64_chars++] = *p; - if (base64_chars == 4) { - unsigned char out[3]; - - base64_chars = 0; + headers_done = 0; + while (1) { + if (!fgets(buffer, sizeof(buffer), fp)) { + errmsg = "Unexpected end of file"; + goto error; + } + if (!strcmp(buffer, "---- END SSH2 ENCRYPTED PRIVATE KEY ----\n")) + break; /* done */ + if ((p = strchr(buffer, ':')) != NULL) { + if (headers_done) { + errmsg = "Header found in body of key data"; + goto error; + } + *p++ = '\0'; + while (*p && isspace((unsigned char)*p)) p++; + /* + * Header lines can end in a trailing backslash for + * continuation. + */ + while ((len = strlen(p)) > (int)(sizeof(buffer) - (p-buffer) -1) || + p[len-1] != '\n' || p[len-2] == '\\') { + if (len > (int)((p-buffer) + sizeof(buffer)-2)) { + errmsg = "Header line too long to deal with"; + goto error; + } + if (!fgets(p+len-2, sizeof(buffer)-(p-buffer)-(len-2), fp)) { + errmsg = "Unexpected end of file"; + goto error; + } + } + p[strcspn(p, "\n")] = '\0'; + if (!strcmp(buffer, "Comment")) { + /* Strip quotes in comment if present. */ + if (p[0] == '"' && p[strlen(p)-1] == '"') { + p++; + p[strlen(p)-1] = '\0'; + } + strncpy(ret->comment, p, sizeof(ret->comment)); + ret->comment[sizeof(ret->comment)-1] = '\0'; + } + } else { + headers_done = 1; - len = base64_decode_atom(base64_bit, out); + p = buffer; + while (isbase64(*p)) { + base64_bit[base64_chars++] = *p; + if (base64_chars == 4) { + unsigned char out[3]; - if (len <= 0) { - errmsg = "Invalid base64 encoding"; - goto error; - } + base64_chars = 0; + + len = base64_decode_atom(base64_bit, out); - if (ret->keyblob_len + len > ret->keyblob_size) { - ret->keyblob_size = ret->keyblob_len + len + 256; - ret->keyblob = sresize(ret->keyblob, ret->keyblob_size, - unsigned char); - } + if (len <= 0) { + errmsg = "Invalid base64 encoding"; + goto error; + } - memcpy(ret->keyblob + ret->keyblob_len, out, len); - ret->keyblob_len += len; - } + if (ret->keyblob_len + len > ret->keyblob_size) { + ret->keyblob_size = ret->keyblob_len + len + 256; + ret->keyblob = sresize(ret->keyblob, ret->keyblob_size, + unsigned char); + } - p++; - } + memcpy(ret->keyblob + ret->keyblob_len, out, len); + ret->keyblob_len += len; + } + + p++; + } + } } - } - if (ret->keyblob_len == 0 || !ret->keyblob) { - errmsg = "Key body not present"; - goto error; - } + if (ret->keyblob_len == 0 || !ret->keyblob) { + errmsg = "Key body not present"; + goto error; + } - return ret; + return ret; - error: - if (ret) { - if (ret->keyblob) { - memset(ret->keyblob, 0, ret->keyblob_size); - m_free(ret->keyblob); - } - memset(ret, 0, sizeof(*ret)); - m_free(ret); - } - return NULL; + error: + if (ret) { + if (ret->keyblob) { + memset(ret->keyblob, 0, ret->keyblob_size); + m_free(ret->keyblob); + } + memset(ret, 0, sizeof(*ret)); + m_free(ret); + } + return NULL; } int sshcom_encrypted(const char *filename, char **comment) { - struct sshcom_key *key = load_sshcom_key(filename); - int pos, len, answer; + struct sshcom_key *key = load_sshcom_key(filename); + int pos, len, answer; - *comment = NULL; - if (!key) - return 0; + *comment = NULL; + if (!key) + return 0; - /* - * Check magic number. - */ - if (GET_32BIT(key->keyblob) != 0x3f6ff9eb) - return 0; /* key is invalid */ + /* + * Check magic number. + */ + if (GET_32BIT(key->keyblob) != 0x3f6ff9eb) + return 0; /* key is invalid */ - /* - * Find the cipher-type string. - */ - answer = 0; - pos = 8; - if (key->keyblob_len < pos+4) - goto done; /* key is far too short */ - len = toint(GET_32BIT(key->keyblob + pos)); - if (len < 0 || len > key->keyblob_len - pos - 4) - goto done; /* key is far too short */ - pos += 4 + len; /* skip key type */ - len = toint(GET_32BIT(key->keyblob + pos)); /* find cipher-type length */ - if (len < 0 || len > key->keyblob_len - pos - 4) - goto done; /* cipher type string is incomplete */ - if (len != 4 || 0 != memcmp(key->keyblob + pos + 4, "none", 4)) - answer = 1; + /* + * Find the cipher-type string. + */ + answer = 0; + pos = 8; + if (key->keyblob_len < pos+4) + goto done; /* key is far too short */ + len = toint(GET_32BIT(key->keyblob + pos)); + if (len < 0 || len > key->keyblob_len - pos - 4) + goto done; /* key is far too short */ + pos += 4 + len; /* skip key type */ + len = toint(GET_32BIT(key->keyblob + pos)); /* find cipher-type length */ + if (len < 0 || len > key->keyblob_len - pos - 4) + goto done; /* cipher type string is incomplete */ + if (len != 4 || 0 != memcmp(key->keyblob + pos + 4, "none", 4)) + answer = 1; - done: - *comment = dupstr(key->comment); - memset(key->keyblob, 0, key->keyblob_size); - m_free(key->keyblob); - memset(key, 0, sizeof(*key)); - m_free(key); - return answer; + done: + *comment = dupstr(key->comment); + memset(key->keyblob, 0, key->keyblob_size); + m_free(key->keyblob); + memset(key, 0, sizeof(*key)); + m_free(key); + return answer; } static int sshcom_read_mpint(void *data, int len, struct mpint_pos *ret) { - unsigned bits, bytes; - unsigned char *d = (unsigned char *) data; + unsigned bits, bytes; + unsigned char *d = (unsigned char *) data; - if (len < 4) - goto error; - bits = GET_32BIT(d); + if (len < 4) + goto error; + bits = GET_32BIT(d); - bytes = (bits + 7) / 8; - if (len < 4+bytes) - goto error; + bytes = (bits + 7) / 8; + if (len < 4+bytes) + goto error; - ret->start = d + 4; - ret->bytes = bytes; - return bytes+4; + ret->start = d + 4; + ret->bytes = bytes; + return bytes+4; - error: - ret->start = NULL; - ret->bytes = -1; - return len; /* ensure further calls fail as well */ + error: + ret->start = NULL; + ret->bytes = -1; + return len; /* ensure further calls fail as well */ } static int sshcom_put_mpint(void *target, void *data, int len) { - unsigned char *d = (unsigned char *)target; - unsigned char *i = (unsigned char *)data; - int bits = len * 8 - 1; + unsigned char *d = (unsigned char *)target; + unsigned char *i = (unsigned char *)data; + int bits = len * 8 - 1; - while (bits > 0) { - if (*i & (1 << (bits & 7))) - break; - if (!(bits-- & 7)) - i++, len--; - } + while (bits > 0) { + if (*i & (1 << (bits & 7))) + break; + if (!(bits-- & 7)) + i++, len--; + } - PUT_32BIT(d, bits+1); - memcpy(d+4, i, len); - return len+4; + PUT_32BIT(d, bits+1); + memcpy(d+4, i, len); + return len+4; } sign_key *sshcom_read(const char *filename, char *passphrase) { - struct sshcom_key *key = load_sshcom_key(filename); - char *errmsg; - int pos, len; - const char prefix_rsa[] = "if-modn{sign{rsa"; - const char prefix_dsa[] = "dl-modp{sign{dsa"; - enum { RSA, DSA } type; - int encrypted; - char *ciphertext; - int cipherlen; - struct ssh2_userkey *ret = NULL, *retkey; - const struct ssh_signkey *alg; - unsigned char *blob = NULL; - int blobsize = 0, publen, privlen; - - if (!key) - return NULL; + struct sshcom_key *key = load_sshcom_key(filename); + char *errmsg; + int pos, len; + const char prefix_rsa[] = "if-modn{sign{rsa"; + const char prefix_dsa[] = "dl-modp{sign{dsa"; + enum { RSA, DSA } type; + int encrypted; + char *ciphertext; + int cipherlen; + struct ssh2_userkey *ret = NULL, *retkey; + const struct ssh_signkey *alg; + unsigned char *blob = NULL; + int blobsize = 0, publen, privlen; - /* - * Check magic number. - */ - if (GET_32BIT(key->keyblob) != SSHCOM_MAGIC_NUMBER) { - errmsg = "Key does not begin with magic number"; - goto error; - } + if (!key) + return NULL; - /* - * Determine the key type. - */ - pos = 8; - if (key->keyblob_len < pos+4 || - (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { - errmsg = "Key blob does not contain a key type string"; - goto error; - } - if (len > sizeof(prefix_rsa) - 1 && - !memcmp(key->keyblob+pos+4, prefix_rsa, sizeof(prefix_rsa) - 1)) { - type = RSA; - } else if (len > sizeof(prefix_dsa) - 1 && - !memcmp(key->keyblob+pos+4, prefix_dsa, sizeof(prefix_dsa) - 1)) { - type = DSA; - } else { - errmsg = "Key is of unknown type"; - goto error; - } - pos += 4+len; + /* + * Check magic number. + */ + if (GET_32BIT(key->keyblob) != SSHCOM_MAGIC_NUMBER) { + errmsg = "Key does not begin with magic number"; + goto error; + } - /* - * Determine the cipher type. - */ - if (key->keyblob_len < pos+4 || - (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { - errmsg = "Key blob does not contain a cipher type string"; - goto error; - } - if (len == 4 && !memcmp(key->keyblob+pos+4, "none", 4)) - encrypted = 0; - else if (len == 8 && !memcmp(key->keyblob+pos+4, "3des-cbc", 8)) - encrypted = 1; - else { - errmsg = "Key encryption is of unknown type"; - goto error; - } - pos += 4+len; + /* + * Determine the key type. + */ + pos = 8; + if (key->keyblob_len < pos+4 || + (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { + errmsg = "Key blob does not contain a key type string"; + goto error; + } + if (len > sizeof(prefix_rsa) - 1 && + !memcmp(key->keyblob+pos+4, prefix_rsa, sizeof(prefix_rsa) - 1)) { + type = RSA; + } else if (len > sizeof(prefix_dsa) - 1 && + !memcmp(key->keyblob+pos+4, prefix_dsa, sizeof(prefix_dsa) - 1)) { + type = DSA; + } else { + errmsg = "Key is of unknown type"; + goto error; + } + pos += 4+len; - /* - * Get hold of the encrypted part of the key. - */ - if (key->keyblob_len < pos+4 || - (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { - errmsg = "Key blob does not contain actual key data"; - goto error; - } - ciphertext = (char *)key->keyblob + pos + 4; - cipherlen = len; - if (cipherlen == 0) { - errmsg = "Length of key data is zero"; - goto error; - } - - /* - * Decrypt it if necessary. - */ - if (encrypted) { /* - * Derive encryption key from passphrase and iv/salt: - * - * - let block A equal MD5(passphrase) - * - let block B equal MD5(passphrase || A) - * - block C would be MD5(passphrase || A || B) and so on - * - encryption key is the first N bytes of A || B + * Determine the cipher type. */ - struct MD5Context md5c; - unsigned char keybuf[32], iv[8]; + if (key->keyblob_len < pos+4 || + (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { + errmsg = "Key blob does not contain a cipher type string"; + goto error; + } + if (len == 4 && !memcmp(key->keyblob+pos+4, "none", 4)) + encrypted = 0; + else if (len == 8 && !memcmp(key->keyblob+pos+4, "3des-cbc", 8)) + encrypted = 1; + else { + errmsg = "Key encryption is of unknown type"; + goto error; + } + pos += 4+len; - if (cipherlen % 8 != 0) { - errmsg = "Encrypted part of key is not a multiple of cipher block" - " size"; - goto error; - } - - MD5Init(&md5c); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Final(keybuf, &md5c); - - MD5Init(&md5c); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Update(&md5c, keybuf, 16); - MD5Final(keybuf+16, &md5c); + /* + * Get hold of the encrypted part of the key. + */ + if (key->keyblob_len < pos+4 || + (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) { + errmsg = "Key blob does not contain actual key data"; + goto error; + } + ciphertext = (char *)key->keyblob + pos + 4; + cipherlen = len; + if (cipherlen == 0) { + errmsg = "Length of key data is zero"; + goto error; + } /* - * Now decrypt the key blob. + * Decrypt it if necessary. */ - memset(iv, 0, sizeof(iv)); - des3_decrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, - cipherlen); - - memset(&md5c, 0, sizeof(md5c)); - memset(keybuf, 0, sizeof(keybuf)); + if (encrypted) { + /* + * Derive encryption key from passphrase and iv/salt: + * + * - let block A equal MD5(passphrase) + * - let block B equal MD5(passphrase || A) + * - block C would be MD5(passphrase || A || B) and so on + * - encryption key is the first N bytes of A || B + */ + struct MD5Context md5c; + unsigned char keybuf[32], iv[8]; - /* - * Hereafter we return WRONG_PASSPHRASE for any parsing - * error. (But only if we've just tried to decrypt it! - * Returning WRONG_PASSPHRASE for an unencrypted key is - * automatic doom.) - */ - if (encrypted) - ret = SSH2_WRONG_PASSPHRASE; - } + if (cipherlen % 8 != 0) { + errmsg = "Encrypted part of key is not a multiple of cipher block" + " size"; + goto error; + } + + MD5Init(&md5c); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Final(keybuf, &md5c); + + MD5Init(&md5c); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Update(&md5c, keybuf, 16); + MD5Final(keybuf+16, &md5c); - /* - * Strip away the containing string to get to the real meat. - */ - len = toint(GET_32BIT(ciphertext)); - if (len < 0 || len > cipherlen-4) { - errmsg = "containing string was ill-formed"; - goto error; - } - ciphertext += 4; - cipherlen = len; + /* + * Now decrypt the key blob. + */ + memset(iv, 0, sizeof(iv)); + des3_decrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, + cipherlen); + + memset(&md5c, 0, sizeof(md5c)); + memset(keybuf, 0, sizeof(keybuf)); - /* - * Now we break down into RSA versus DSA. In either case we'll - * construct public and private blobs in our own format, and - * end up feeding them to alg->createkey(). - */ - blobsize = cipherlen + 256; - blob = snewn(blobsize, unsigned char); - privlen = 0; - if (type == RSA) { - struct mpint_pos n, e, d, u, p, q; - int pos = 0; - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &e); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &d); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &n); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &u); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); - if (!q.start) { - errmsg = "key data did not contain six integers"; - goto error; - } + /* + * Hereafter we return WRONG_PASSPHRASE for any parsing + * error. (But only if we've just tried to decrypt it! + * Returning WRONG_PASSPHRASE for an unencrypted key is + * automatic doom.) + */ + if (encrypted) + ret = SSH2_WRONG_PASSPHRASE; + } + + /* + * Strip away the containing string to get to the real meat. + */ + len = toint(GET_32BIT(ciphertext)); + if (len < 0 || len > cipherlen-4) { + errmsg = "containing string was ill-formed"; + goto error; + } + ciphertext += 4; + cipherlen = len; - alg = &ssh_rsa; - pos = 0; - pos += put_string(blob+pos, "ssh-rsa", 7); - pos += put_mp(blob+pos, e.start, e.bytes); - pos += put_mp(blob+pos, n.start, n.bytes); - publen = pos; - pos += put_string(blob+pos, d.start, d.bytes); - pos += put_mp(blob+pos, q.start, q.bytes); - pos += put_mp(blob+pos, p.start, p.bytes); - pos += put_mp(blob+pos, u.start, u.bytes); - privlen = pos - publen; - } else if (type == DSA) { - struct mpint_pos p, q, g, x, y; - int pos = 4; - if (GET_32BIT(ciphertext) != 0) { - errmsg = "predefined DSA parameters not supported"; - goto error; - } - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &g); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &y); - pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &x); - if (!x.start) { - errmsg = "key data did not contain five integers"; - goto error; - } + /* + * Now we break down into RSA versus DSA. In either case we'll + * construct public and private blobs in our own format, and + * end up feeding them to alg->createkey(). + */ + blobsize = cipherlen + 256; + blob = snewn(blobsize, unsigned char); + privlen = 0; + if (type == RSA) { + struct mpint_pos n, e, d, u, p, q; + int pos = 0; + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &e); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &d); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &n); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &u); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); + if (!q.start) { + errmsg = "key data did not contain six integers"; + goto error; + } - alg = &ssh_dss; - pos = 0; - pos += put_string(blob+pos, "ssh-dss", 7); - pos += put_mp(blob+pos, p.start, p.bytes); - pos += put_mp(blob+pos, q.start, q.bytes); - pos += put_mp(blob+pos, g.start, g.bytes); - pos += put_mp(blob+pos, y.start, y.bytes); - publen = pos; - pos += put_mp(blob+pos, x.start, x.bytes); - privlen = pos - publen; - } else - return NULL; - - dropbear_assert(privlen > 0); /* should have bombed by now if not */ + alg = &ssh_rsa; + pos = 0; + pos += put_string(blob+pos, "ssh-rsa", 7); + pos += put_mp(blob+pos, e.start, e.bytes); + pos += put_mp(blob+pos, n.start, n.bytes); + publen = pos; + pos += put_string(blob+pos, d.start, d.bytes); + pos += put_mp(blob+pos, q.start, q.bytes); + pos += put_mp(blob+pos, p.start, p.bytes); + pos += put_mp(blob+pos, u.start, u.bytes); + privlen = pos - publen; + } else if (type == DSA) { + struct mpint_pos p, q, g, x, y; + int pos = 4; + if (GET_32BIT(ciphertext) != 0) { + errmsg = "predefined DSA parameters not supported"; + goto error; + } + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &p); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &g); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &q); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &y); + pos += sshcom_read_mpint(ciphertext+pos, cipherlen-pos, &x); + if (!x.start) { + errmsg = "key data did not contain five integers"; + goto error; + } - retkey = snew(struct ssh2_userkey); - retkey->alg = alg; - retkey->data = alg->createkey(blob, publen, blob+publen, privlen); - if (!retkey->data) { - m_free(retkey); - errmsg = "unable to create key data structure"; - goto error; - } - retkey->comment = dupstr(key->comment); + alg = &ssh_dss; + pos = 0; + pos += put_string(blob+pos, "ssh-dss", 7); + pos += put_mp(blob+pos, p.start, p.bytes); + pos += put_mp(blob+pos, q.start, q.bytes); + pos += put_mp(blob+pos, g.start, g.bytes); + pos += put_mp(blob+pos, y.start, y.bytes); + publen = pos; + pos += put_mp(blob+pos, x.start, x.bytes); + privlen = pos - publen; + } else + return NULL; + + dropbear_assert(privlen > 0); /* should have bombed by now if not */ - errmsg = NULL; /* no error */ - ret = retkey; + retkey = snew(struct ssh2_userkey); + retkey->alg = alg; + retkey->data = alg->createkey(blob, publen, blob+publen, privlen); + if (!retkey->data) { + m_free(retkey); + errmsg = "unable to create key data structure"; + goto error; + } + retkey->comment = dupstr(key->comment); - error: - if (blob) { - memset(blob, 0, blobsize); - m_free(blob); - } - memset(key->keyblob, 0, key->keyblob_size); - m_free(key->keyblob); - memset(key, 0, sizeof(*key)); - m_free(key); - return ret; + errmsg = NULL; /* no error */ + ret = retkey; + + error: + if (blob) { + memset(blob, 0, blobsize); + m_free(blob); + } + memset(key->keyblob, 0, key->keyblob_size); + m_free(key->keyblob); + memset(key, 0, sizeof(*key)); + m_free(key); + return ret; } int sshcom_write(const char *filename, sign_key *key, - char *passphrase) + char *passphrase) { - unsigned char *pubblob, *privblob; - int publen, privlen; - unsigned char *outblob; - int outlen; - struct mpint_pos numbers[6]; - int nnumbers, initial_zero, pos, lenpos, i; - char *type; - char *ciphertext; - int cipherlen; - int ret = 0; - FILE *fp; - - /* - * Fetch the key blobs. - */ - pubblob = key->alg->public_blob(key->data, &publen); - privblob = key->alg->private_blob(key->data, &privlen); - outblob = NULL; - - /* - * Find the sequence of integers to be encoded into the OpenSSH - * key blob, and also decide on the header line. - */ - if (key->alg == &ssh_rsa) { - int pos; - struct mpint_pos n, e, d, p, q, iqmp; + unsigned char *pubblob, *privblob; + int publen, privlen; + unsigned char *outblob; + int outlen; + struct mpint_pos numbers[6]; + int nnumbers, initial_zero, pos, lenpos, i; + char *type; + char *ciphertext; + int cipherlen; + int ret = 0; + FILE *fp; - pos = 4 + GET_32BIT(pubblob); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n); - pos = 0; - pos += ssh2_read_mpint(privblob+pos, privlen-pos, &d); - pos += ssh2_read_mpint(privblob+pos, privlen-pos, &p); - pos += ssh2_read_mpint(privblob+pos, privlen-pos, &q); - pos += ssh2_read_mpint(privblob+pos, privlen-pos, &iqmp); - - dropbear_assert(e.start && iqmp.start); /* can't go wrong */ - - numbers[0] = e; - numbers[1] = d; - numbers[2] = n; - numbers[3] = iqmp; - numbers[4] = q; - numbers[5] = p; + /* + * Fetch the key blobs. + */ + pubblob = key->alg->public_blob(key->data, &publen); + privblob = key->alg->private_blob(key->data, &privlen); + outblob = NULL; - nnumbers = 6; - initial_zero = 0; - type = "if-modn{sign{rsa-pkcs1-sha1},encrypt{rsa-pkcs1v2-oaep}}"; - } else if (key->alg == &ssh_dss) { - int pos; - struct mpint_pos p, q, g, y, x; + /* + * Find the sequence of integers to be encoded into the OpenSSH + * key blob, and also decide on the header line. + */ + if (key->alg == &ssh_rsa) { + int pos; + struct mpint_pos n, e, d, p, q, iqmp; - pos = 4 + GET_32BIT(pubblob); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &g); - pos += ssh2_read_mpint(pubblob+pos, publen-pos, &y); - pos = 0; - pos += ssh2_read_mpint(privblob+pos, privlen-pos, &x); + pos = 4 + GET_32BIT(pubblob); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n); + pos = 0; + pos += ssh2_read_mpint(privblob+pos, privlen-pos, &d); + pos += ssh2_read_mpint(privblob+pos, privlen-pos, &p); + pos += ssh2_read_mpint(privblob+pos, privlen-pos, &q); + pos += ssh2_read_mpint(privblob+pos, privlen-pos, &iqmp); - dropbear_assert(y.start && x.start); /* can't go wrong */ - - numbers[0] = p; - numbers[1] = g; - numbers[2] = q; - numbers[3] = y; - numbers[4] = x; + dropbear_assert(e.start && iqmp.start); /* can't go wrong */ - nnumbers = 5; - initial_zero = 1; - type = "dl-modp{sign{dsa-nist-sha1},dh{plain}}"; - } else { - dropbear_assert(0); /* zoinks! */ - } + numbers[0] = e; + numbers[1] = d; + numbers[2] = n; + numbers[3] = iqmp; + numbers[4] = q; + numbers[5] = p; - /* - * Total size of key blob will be somewhere under 512 plus - * combined length of integers. We'll calculate the more - * precise size as we construct the blob. - */ - outlen = 512; - for (i = 0; i < nnumbers; i++) - outlen += 4 + numbers[i].bytes; - outblob = snewn(outlen, unsigned char); + nnumbers = 6; + initial_zero = 0; + type = "if-modn{sign{rsa-pkcs1-sha1},encrypt{rsa-pkcs1v2-oaep}}"; + } else if (key->alg == &ssh_dss) { + int pos; + struct mpint_pos p, q, g, y, x; + + pos = 4 + GET_32BIT(pubblob); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &g); + pos += ssh2_read_mpint(pubblob+pos, publen-pos, &y); + pos = 0; + pos += ssh2_read_mpint(privblob+pos, privlen-pos, &x); - /* - * Create the unencrypted key blob. - */ - pos = 0; - PUT_32BIT(outblob+pos, SSHCOM_MAGIC_NUMBER); pos += 4; - pos += 4; /* length field, fill in later */ - pos += put_string(outblob+pos, type, strlen(type)); - { - char *ciphertype = passphrase ? "3des-cbc" : "none"; - pos += put_string(outblob+pos, ciphertype, strlen(ciphertype)); - } - lenpos = pos; /* remember this position */ - pos += 4; /* encrypted-blob size */ - pos += 4; /* encrypted-payload size */ - if (initial_zero) { - PUT_32BIT(outblob+pos, 0); - pos += 4; - } - for (i = 0; i < nnumbers; i++) - pos += sshcom_put_mpint(outblob+pos, - numbers[i].start, numbers[i].bytes); - /* Now wrap up the encrypted payload. */ - PUT_32BIT(outblob+lenpos+4, pos - (lenpos+8)); - /* Pad encrypted blob to a multiple of cipher block size. */ - if (passphrase) { - int padding = -(pos - (lenpos+4)) & 7; - while (padding--) - outblob[pos++] = random_byte(); - } - ciphertext = (char *)outblob+lenpos+4; - cipherlen = pos - (lenpos+4); - dropbear_assert(!passphrase || cipherlen % 8 == 0); - /* Wrap up the encrypted blob string. */ - PUT_32BIT(outblob+lenpos, cipherlen); - /* And finally fill in the total length field. */ - PUT_32BIT(outblob+4, pos); + dropbear_assert(y.start && x.start); /* can't go wrong */ + + numbers[0] = p; + numbers[1] = g; + numbers[2] = q; + numbers[3] = y; + numbers[4] = x; - dropbear_assert(pos < outlen); + nnumbers = 5; + initial_zero = 1; + type = "dl-modp{sign{dsa-nist-sha1},dh{plain}}"; + } else { + dropbear_assert(0); /* zoinks! */ + } - /* - * Encrypt the key. - */ - if (passphrase) { /* - * Derive encryption key from passphrase and iv/salt: - * - * - let block A equal MD5(passphrase) - * - let block B equal MD5(passphrase || A) - * - block C would be MD5(passphrase || A || B) and so on - * - encryption key is the first N bytes of A || B + * Total size of key blob will be somewhere under 512 plus + * combined length of integers. We'll calculate the more + * precise size as we construct the blob. */ - struct MD5Context md5c; - unsigned char keybuf[32], iv[8]; - - MD5Init(&md5c); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Final(keybuf, &md5c); - - MD5Init(&md5c); - MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); - MD5Update(&md5c, keybuf, 16); - MD5Final(keybuf+16, &md5c); + outlen = 512; + for (i = 0; i < nnumbers; i++) + outlen += 4 + numbers[i].bytes; + outblob = snewn(outlen, unsigned char); /* - * Now decrypt the key blob. + * Create the unencrypted key blob. */ - memset(iv, 0, sizeof(iv)); - des3_encrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, - cipherlen); + pos = 0; + PUT_32BIT(outblob+pos, SSHCOM_MAGIC_NUMBER); pos += 4; + pos += 4; /* length field, fill in later */ + pos += put_string(outblob+pos, type, strlen(type)); + { + char *ciphertype = passphrase ? "3des-cbc" : "none"; + pos += put_string(outblob+pos, ciphertype, strlen(ciphertype)); + } + lenpos = pos; /* remember this position */ + pos += 4; /* encrypted-blob size */ + pos += 4; /* encrypted-payload size */ + if (initial_zero) { + PUT_32BIT(outblob+pos, 0); + pos += 4; + } + for (i = 0; i < nnumbers; i++) + pos += sshcom_put_mpint(outblob+pos, + numbers[i].start, numbers[i].bytes); + /* Now wrap up the encrypted payload. */ + PUT_32BIT(outblob+lenpos+4, pos - (lenpos+8)); + /* Pad encrypted blob to a multiple of cipher block size. */ + if (passphrase) { + int padding = -(pos - (lenpos+4)) & 7; + while (padding--) + outblob[pos++] = random_byte(); + } + ciphertext = (char *)outblob+lenpos+4; + cipherlen = pos - (lenpos+4); + dropbear_assert(!passphrase || cipherlen % 8 == 0); + /* Wrap up the encrypted blob string. */ + PUT_32BIT(outblob+lenpos, cipherlen); + /* And finally fill in the total length field. */ + PUT_32BIT(outblob+4, pos); - memset(&md5c, 0, sizeof(md5c)); - memset(keybuf, 0, sizeof(keybuf)); - } + dropbear_assert(pos < outlen); + + /* + * Encrypt the key. + */ + if (passphrase) { + /* + * Derive encryption key from passphrase and iv/salt: + * + * - let block A equal MD5(passphrase) + * - let block B equal MD5(passphrase || A) + * - block C would be MD5(passphrase || A || B) and so on + * - encryption key is the first N bytes of A || B + */ + struct MD5Context md5c; + unsigned char keybuf[32], iv[8]; + + MD5Init(&md5c); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Final(keybuf, &md5c); - /* - * And save it. We'll use Unix line endings just in case it's - * subsequently transferred in binary mode. - */ - fp = fopen(filename, "wb"); /* ensure Unix line endings */ - if (!fp) - goto error; - fputs("---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); - fprintf(fp, "Comment: \""); - /* - * Comment header is broken with backslash-newline if it goes - * over 70 chars. Although it's surrounded by quotes, it - * _doesn't_ escape backslashes or quotes within the string. - * Don't ask me, I didn't design it. - */ - { - int slen = 60; /* starts at 60 due to "Comment: " */ - char *c = key->comment; - while ((int)strlen(c) > slen) { - fprintf(fp, "%.*s\\\n", slen, c); - c += slen; - slen = 70; /* allow 70 chars on subsequent lines */ + MD5Init(&md5c); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); + MD5Update(&md5c, keybuf, 16); + MD5Final(keybuf+16, &md5c); + + /* + * Now decrypt the key blob. + */ + memset(iv, 0, sizeof(iv)); + des3_encrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext, + cipherlen); + + memset(&md5c, 0, sizeof(md5c)); + memset(keybuf, 0, sizeof(keybuf)); } - fprintf(fp, "%s\"\n", c); - } - base64_encode_fp(fp, outblob, pos, 70); - fputs("---- END SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); - fclose(fp); - ret = 1; - error: - if (outblob) { - memset(outblob, 0, outlen); - m_free(outblob); - } - if (privblob) { - memset(privblob, 0, privlen); - m_free(privblob); - } - if (pubblob) { - memset(pubblob, 0, publen); - m_free(pubblob); - } - return ret; + /* + * And save it. We'll use Unix line endings just in case it's + * subsequently transferred in binary mode. + */ + fp = fopen(filename, "wb"); /* ensure Unix line endings */ + if (!fp) + goto error; + fputs("---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); + fprintf(fp, "Comment: \""); + /* + * Comment header is broken with backslash-newline if it goes + * over 70 chars. Although it's surrounded by quotes, it + * _doesn't_ escape backslashes or quotes within the string. + * Don't ask me, I didn't design it. + */ + { + int slen = 60; /* starts at 60 due to "Comment: " */ + char *c = key->comment; + while ((int)strlen(c) > slen) { + fprintf(fp, "%.*s\\\n", slen, c); + c += slen; + slen = 70; /* allow 70 chars on subsequent lines */ + } + fprintf(fp, "%s\"\n", c); + } + base64_encode_fp(fp, outblob, pos, 70); + fputs("---- END SSH2 ENCRYPTED PRIVATE KEY ----\n", fp); + fclose(fp); + ret = 1; + + error: + if (outblob) { + memset(outblob, 0, outlen); + m_free(outblob); + } + if (privblob) { + memset(privblob, 0, privlen); + m_free(privblob); + } + if (pubblob) { + memset(pubblob, 0, publen); + m_free(pubblob); + } + return ret; } #endif /* ssh.com stuff disabled */ /* From PuTTY misc.c */ static int toint(unsigned u) { - /* - * Convert an unsigned to an int, without running into the - * undefined behaviour which happens by the strict C standard if - * the value overflows. You'd hope that sensible compilers would - * do the sensible thing in response to a cast, but actually I - * don't trust modern compilers not to do silly things like - * assuming that _obviously_ you wouldn't have caused an overflow - * and so they can elide an 'if (i < 0)' test immediately after - * the cast. - * - * Sensible compilers ought of course to optimise this entire - * function into 'just return the input value'! - */ - if (u <= (unsigned)INT_MAX) - return (int)u; - else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */ - return INT_MIN + (int)(u - (unsigned)INT_MIN); - else - return INT_MIN; /* fallback; should never occur on binary machines */ + /* + * Convert an unsigned to an int, without running into the + * undefined behaviour which happens by the strict C standard if + * the value overflows. You'd hope that sensible compilers would + * do the sensible thing in response to a cast, but actually I + * don't trust modern compilers not to do silly things like + * assuming that _obviously_ you wouldn't have caused an overflow + * and so they can elide an 'if (i < 0)' test immediately after + * the cast. + * + * Sensible compilers ought of course to optimise this entire + * function into 'just return the input value'! + */ + if (u <= (unsigned)INT_MAX) + return (int)u; + else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */ + return INT_MIN + (int)(u - (unsigned)INT_MIN); + else + return INT_MIN; /* fallback; should never occur on binary machines */ }