/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. * * Copyright 2014 Nexenta Systems, Inc. All rights reserved. */ #if defined(_KERNEL) || defined(_FAKE_KERNEL) #include <sys/types.h> #include <sys/sunddi.h> #else #include <string.h> #endif #include <smbsrv/string.h> #include <smbsrv/netbios.h> /* * Routines than support name compression. * * The NetBIOS name representation in all NetBIOS packets (for NAME, * SESSION, and DATAGRAM services) is defined in the Domain Name * Service RFC 883[3] as "compressed" name messages. This format is * called "second-level encoding" in the section entitled * "Representation of NetBIOS Names" in the Concepts and Methods * document. * * For ease of description, the first two paragraphs from page 31, * the section titled "Domain name representation and compression", * of RFC 883 are replicated here: * * Domain names messages are expressed in terms of a sequence * of labels. Each label is represented as a one octet length * field followed by that number of octets. Since every domain * name ends with the null label of the root, a compressed * domain name is terminated by a length byte of zero. The * high order two bits of the length field must be zero, and * the remaining six bits of the length field limit the label * to 63 octets or less. * * To simplify implementations, the total length of label * octets and label length octets that make up a domain name is * restricted to 255 octets or less. * * The following is the uncompressed representation of the NetBIOS name * "FRED ", which is the 4 ASCII characters, F, R, E, D, followed by 12 * space characters (0x20). This name has the SCOPE_ID: "NETBIOS.COM" * * EGFCEFEECACACACACACACACACACACACA.NETBIOS.COM * * This uncompressed representation of names is called "first-level * encoding" in the section entitled "Representation of NetBIOS Names" * in the Concepts and Methods document. * * The following is a pictographic representation of the compressed * representation of the previous uncompressed Domain Name * representation. * * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | 0x20 | E (0x45) | G (0x47) | F (0x46) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | C (0x43) | E (0x45) | F (0x46) | E (0x45) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | E (0x45) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0x41) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0x41) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0x41) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0x41) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0x41) | C (0x43) | A (0x41) | C (0x43) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | A (0X41) | 0x07 | N (0x4E) | E (0x45) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | T (0x54) | B (0x42) | I (0x49) | O (0x4F) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | S (0x53) | 0x03 | C (0x43) | O (0x4F) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | M (0x4D) | 0x00 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * Each section of a domain name is called a label [7 (page 31)]. A * label can be a maximum of 63 bytes. The first byte of a label in * compressed representation is the number of bytes in the label. For * the above example, the first 0x20 is the number of bytes in the * left-most label, EGFCEFEECACACACACACACACACACACACA, of the domain * name. The bytes following the label length count are the characters * of the label. The following labels are in sequence after the first * label, which is the encoded NetBIOS name, until a zero (0x00) length * count. The zero length count represents the root label, which is * always null. * * A label length count is actually a 6-bit field in the label length * field. The most significant 2 bits of the field, bits 7 and 6, are * flags allowing an escape from the above compressed representation. * If bits 7 and 6 are both set (11), the following 14 bits are an * offset pointer into the full message to the actual label string from * another domain name that belongs in this name. This label pointer * allows for a further compression of a domain name in a packet. * * NetBIOS implementations can only use label string pointers in Name * Service packets. They cannot be used in Session or Datagram Service * packets. * * The other two possible values for bits 7 and 6 (01 and 10) of a label * length field are reserved for future use by RFC 883[2 (page 32)]. * * Note that the first octet of a compressed name must contain one of * the following bit patterns. (An "x" indicates a bit whose value may * be either 0 or 1.): * * 00100000 - Netbios name, length must be 32 (decimal) * 11xxxxxx - Label string pointer * 10xxxxxx - Reserved * 01xxxxxx - Reserved */ /* * netbios_first_level_name_encode * * Put test description here. * * Inputs: * char * in -> Name to encode * char * out -> Buffer to encode into. * int length -> # of bytes to encode. * * Returns: * Nothing */ int netbios_first_level_name_encode(unsigned char *name, unsigned char *scope, unsigned char *out, int max_out) { unsigned char ch, len; unsigned char *in; unsigned char *lp; unsigned char *op = out; if (max_out < 0x21) return (-1); in = name; *op++ = 0x20; for (len = 0; len < NETBIOS_NAME_SZ; len++) { ch = *in++; *op++ = 'A' + ((ch >> 4) & 0xF); *op++ = 'A' + ((ch) & 0xF); } max_out -= 0x21; in = scope; len = 0; lp = op++; while (((ch = *in++) != 0) && (max_out-- > 1)) { if (ch == 0) { if ((*lp = len) != 0) *op++ = 0; break; } if (ch == '.') { *lp = len; lp = op++; len = 0; } else { *op++ = ch; len++; } } *lp = len; if (len != 0) *op = 0; /*LINTED E_PTRDIFF_OVERFLOW*/ return (op - out); } /* * smb_first_level_name_decode * * The null terminated string "in" is the name to decode. The output * is placed in the name_entry structure "name". * * The scope field is a series of length designated labels as described * in the "Domain name representation and compression" section of RFC883. * The two high order two bits of the length field must be zero, the * remaining six bits contain the field length. The total length of the * domain name is restricted to 255 octets but note that the trailing * root label and its dot are not printed. When converting the labels, * the length fields are replaced by dots. * * Returns the number of bytes scanned or -1 to indicate an error. */ int netbios_first_level_name_decode(char *in, char *name, char *scope) { unsigned int length; char c1, c2; char *cp; char *out; cp = in; if ((length = *cp++) != 0x20) { return (-1); } out = name; while (length > 0) { c1 = *cp++; c2 = *cp++; if ('A' <= c1 && c1 <= 'P' && 'A' <= c2 && c2 <= 'P') { c1 -= 'A'; c2 -= 'A'; *out++ = (c1 << 4) | (c2); } else { return (-1); /* conversion error */ } length -= 2; } /* * Don't bother decoding the scope. Not supported. */ if ((length = *cp++) != 0) return (-1); scope[0] = '\0'; /*LINTED E_PTRDIFF_OVERFLOW*/ return (cp - in); } /* * smb_netbios_name_isvalid * * This function is provided to be used by session service * which runs in kernel in order to hide name_entry definition. * * It returns the decoded name in the provided buffer as 'out' * if it's not null. * * Returns 0 if decode fails, 1 if it succeeds. */ int netbios_name_isvalid(char *in, char *out) { char name[NETBIOS_NAME_SZ]; char scope[NETBIOS_DOMAIN_NAME_MAX]; if (netbios_first_level_name_decode(in, name, scope) < 0) return (0); if (out) (void) strlcpy(out, name, NETBIOS_NAME_SZ); return (1); }
