/* $OpenBSD: field.c,v 1.18 2005/11/14 23:25:11 deraadt Exp $ */ /* $EOM: field.c,v 1.11 2000/02/20 19:58:37 niklas Exp $ */ /* * Copyright (c) 1998, 1999 Niklas Hallqvist. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * This code was written under funding by Ericsson Radio Systems. */ #include #include #include #include "constants.h" #include "field.h" #include "log.h" #include "util.h" static char *field_debug_raw(u_int8_t *, size_t, struct constant_map **); static char *field_debug_num(u_int8_t *, size_t, struct constant_map **); static char *field_debug_mask(u_int8_t *, size_t, struct constant_map **); static char *field_debug_ign(u_int8_t *, size_t, struct constant_map **); static char *field_debug_cst(u_int8_t *, size_t, struct constant_map **); /* Contents must match the enum in struct field. */ static char *(*decode_field[]) (u_int8_t *, size_t, struct constant_map **) = { field_debug_raw, field_debug_num, field_debug_mask, field_debug_ign, field_debug_cst }; /* * Return a string showing the hexadecimal contents of the LEN-sized buffer * BUF. MAPS should be zero and is only here because the API requires it. */ static char * field_debug_raw(u_int8_t *buf, size_t len, struct constant_map **maps) { char *retval, *p; if (len == 0) return 0; retval = malloc(3 + len * 2); if (!retval) return 0; strlcpy(retval, "0x", 3 + len * 2); p = retval + 2; for (; len > 0; len--) { snprintf(p, 1 + len * 2, "%02x", *buf++); p += 2; } return retval; } /* * Convert the unsigned LEN-sized number at BUF of network byteorder to a * 32-bit unsigned integer of host byteorder pointed to by VAL. */ static int extract_val(u_int8_t *buf, size_t len, u_int32_t *val) { switch (len) { case 1: *val = *buf; break; case 2: *val = decode_16(buf); break; case 4: *val = decode_32(buf); break; default: return -1; } return 0; } /* * Return a textual representation of the unsigned number pointed to by BUF * which is LEN octets long. MAPS should be zero and is only here because * the API requires it. */ static char * field_debug_num(u_int8_t *buf, size_t len, struct constant_map **maps) { char *retval; u_int32_t val; if (extract_val(buf, len, &val)) return 0; /* 3 decimal digits are enough to represent each byte. */ asprintf(&retval, "%u", val); return retval; } /* * Return the symbolic names of the flags pointed to by BUF which is LEN * octets long, using the constant maps MAPS. */ static char * field_debug_mask(u_int8_t *buf, size_t len, struct constant_map **maps) { u_int32_t val; u_int32_t bit; char *retval, *new_buf, *name; size_t buf_sz; if (extract_val(buf, len, &val)) return 0; /* Size for brackets, two spaces and a NUL terminator. */ buf_sz = 4; retval = malloc(buf_sz); if (!retval) return 0; strlcpy(retval, "[ ", buf_sz); for (bit = 1; bit; bit <<= 1) { if (val & bit) { name = constant_name_maps(maps, bit); buf_sz += strlen(name) + 1; new_buf = realloc(retval, buf_sz); if (!new_buf) { free(retval); return 0; } retval = new_buf; strlcat(retval, name, buf_sz); strlcat(retval, " ", buf_sz); } } strlcat(retval, "]", buf_sz); return retval; } /* * Just a dummy needed to skip the unused LEN sized space at BUF. MAPS * should be zero and is only here because the API requires it. */ static char * field_debug_ign(u_int8_t *buf, size_t len, struct constant_map **maps) { return 0; } /* * Return the symbolic name of a constant pointed to by BUF which is LEN * octets long, using the constant maps MAPS. */ static char * field_debug_cst(u_int8_t *buf, size_t len, struct constant_map **maps) { u_int32_t val; if (extract_val(buf, len, &val)) return 0; return strdup(constant_name_maps(maps, val)); } /* Pretty-print a field from BUF as described by F. */ void field_dump_field(struct field *f, u_int8_t *buf) { char *value; value = decode_field[(int) f->type] (buf + f->offset, f->len, f->maps); if (value) { LOG_DBG((LOG_MESSAGE, 70, "%s: %s", f->name, value)); free(value); } } /* Pretty-print all the fields of BUF as described in FIELDS. */ void field_dump_payload(struct field *fields, u_int8_t *buf) { struct field *field; for (field = fields; field->name; field++) field_dump_field(field, buf); } /* Return the numeric value of the field F of BUF. */ u_int32_t field_get_num(struct field *f, u_int8_t *buf) { u_int32_t val; if (extract_val(buf + f->offset, f->len, &val)) return 0; return val; } /* Stash the number VAL into BUF's field F. */ void field_set_num(struct field *f, u_int8_t *buf, u_int32_t val) { switch (f->len) { case 1: buf[f->offset] = val; break; case 2: encode_16(buf + f->offset, val); break; case 4: encode_32(buf + f->offset, val); break; } } /* Stash BUF's raw field F into VAL. */ void field_get_raw(struct field *f, u_int8_t *buf, u_int8_t *val) { memcpy(val, buf + f->offset, f->len); } /* Stash the buffer VAL into BUF's field F. */ void field_set_raw(struct field *f, u_int8_t *buf, u_int8_t *val) { memcpy(buf + f->offset, val, f->len); }