diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | Makefile.am | 2 | ||||
| -rw-r--r-- | configure.ac | 3 | ||||
| -rw-r--r-- | libwmc/Makefile.am | 2 | ||||
| -rw-r--r-- | libwmc/src/Makefile.am | 28 | ||||
| -rw-r--r-- | libwmc/src/utils.c | 374 | ||||
| -rw-r--r-- | libwmc/src/utils.h | 64 | ||||
| -rw-r--r-- | libwmc/tests/Makefile.am | 28 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-crc.c | 65 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-crc.h | 25 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-escaping.c | 124 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-escaping.h | 26 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-utils.c | 107 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc-utils.h | 28 | ||||
| -rw-r--r-- | libwmc/tests/test-wmc.c | 54 | ||||
| -rw-r--r-- | libwmc/uml290.txt (renamed from uml290.txt) | 63 |
16 files changed, 983 insertions, 11 deletions
@@ -38,6 +38,7 @@ policy/org.freedesktop.modem-manager.policy include/ libqcdm/tests/test-qcdm +libwmc/tests/test-wmc po/Makefile.in.in po/POTFILES diff --git a/Makefile.am b/Makefile.am index 40047146..0962e348 100644 --- a/Makefile.am +++ b/Makefile.am @@ -20,7 +20,7 @@ all: $(GENERATED_FILES) CLEANFILES = $(GENERATED_FILES) endif -SUBDIRS = . marshallers libqcdm src plugins introspection po policy test +SUBDIRS = . marshallers libqcdm libwmc src plugins introspection po policy test if WITH_POLKIT SUBDIRS += policy diff --git a/configure.ac b/configure.ac index 4e06c2ab..567ccf5f 100644 --- a/configure.ac +++ b/configure.ac @@ -143,6 +143,9 @@ marshallers/Makefile libqcdm/Makefile libqcdm/src/Makefile libqcdm/tests/Makefile +libwmc/Makefile +libwmc/src/Makefile +libwmc/tests/Makefile src/Makefile src/tests/Makefile plugins/Makefile diff --git a/libwmc/Makefile.am b/libwmc/Makefile.am new file mode 100644 index 00000000..77f28d7a --- /dev/null +++ b/libwmc/Makefile.am @@ -0,0 +1,2 @@ +SUBDIRS=src tests + diff --git a/libwmc/src/Makefile.am b/libwmc/src/Makefile.am new file mode 100644 index 00000000..fe0a9fbc --- /dev/null +++ b/libwmc/src/Makefile.am @@ -0,0 +1,28 @@ +noinst_LTLIBRARIES = libwmc.la libwmc-test.la + + +libwmc_la_CPPFLAGS = \ + $(MM_CFLAGS) + +libwmc_la_SOURCES = \ + utils.c \ + utils.h + +libwmc_la_LIBADD = \ + $(MM_LIBS) + + +########################################### +# Test library without symbol versioning +########################################### + +libwmc_test_la_CPPFLAGS = \ + $(MM_CFLAGS) + +libwmc_test_la_SOURCES = \ + utils.c \ + utils.h + +libwmc_test_la_LIBADD = \ + $(MM_LIBS) + diff --git a/libwmc/src/utils.c b/libwmc/src/utils.c new file mode 100644 index 00000000..71f8a461 --- /dev/null +++ b/libwmc/src/utils.c @@ -0,0 +1,374 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <stdio.h> +#include <sys/types.h> +#include <unistd.h> +#include <malloc.h> +#include <fcntl.h> +#include <string.h> + +#include "utils.h" + +/* QCDM protocol frames are pseudo Async HDLC frames which end with a 3-byte + * trailer. This trailer consists of the 16-bit CRC of the frame plus an ending + * "async control character" whose value is 0x7E. The frame *and* the CRC are + * escaped before adding the trailing control character so that the control + * character (0x7E) and the escape marker (0x7D) are never seen in the frame. + */ + +/* Table of CRCs for each possible byte, with a generator polynomial of 0x8408 */ +const guint16 crc_table[256] = { + 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, + 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, + 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, + 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, + 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, + 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, + 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, + 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, + 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, + 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, + 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, + 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, + 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, + 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, + 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, + 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, + 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, + 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, + 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, + 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, + 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, + 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, + 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, + 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, + 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, + 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, + 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, + 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, + 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, + 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, + 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, + 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 +}; + +/* Calculate the CRC for a buffer using a seed of 0xffff */ +guint16 +crc16 (const char *buffer, gsize len, guint16 seed) +{ + guint16 crc = seed ? seed : 0xFFFF; + + while (len--) + crc = crc_table[(crc ^ *buffer++) & 0xff] ^ (crc >> 8); + return ~crc; +} + +#define DIAG_ESC_CHAR 0x7D /* Escape sequence 1st character value */ +#define DIAG_ESC_MASK 0x20 /* Escape sequence complement value */ + +/* Performs DM escaping on inbuf putting the result into outbuf, and returns + * the final length of the buffer. + */ +gsize +hdlc_escape (const char *inbuf, + gsize inbuf_len, + gboolean escape_all_ctrl, + char *outbuf, + gsize outbuf_len) +{ + const char *src = inbuf; + char *dst = outbuf; + size_t i = inbuf_len; + + g_return_val_if_fail (inbuf != NULL, 0); + g_return_val_if_fail (inbuf_len > 0, 0); + g_return_val_if_fail (outbuf != NULL, 0); + g_return_val_if_fail (outbuf_len > inbuf_len, 0); + + /* Since escaping potentially doubles the # of bytes, short-circuit the + * length check if destination buffer is clearly large enough. Note the + * + */ + if (outbuf_len <= inbuf_len << 1) { + size_t outbuf_required = inbuf_len + 1; /* +1 for the trailing control char */ + + /* Each escaped character takes up two bytes in the output buffer */ + while (i--) { + if ( *src == DIAG_CONTROL_CHAR + || *src == DIAG_ESC_CHAR + || (escape_all_ctrl && *src <= 0x20)) + outbuf_required++; + src++; + } + + if (outbuf_len < outbuf_required) + return 0; + } + + /* Do the actual escaping. Replace both the control character and + * the escape character in the source buffer with the following sequence: + * + * <escape_char> <src_byte ^ escape_mask> + */ + src = inbuf; + i = inbuf_len; + while (i--) { + if ( *src == DIAG_CONTROL_CHAR + || *src == DIAG_ESC_CHAR + || (escape_all_ctrl && *src <= 0x20)) { + *dst++ = DIAG_ESC_CHAR; + *dst++ = *src ^ DIAG_ESC_MASK; + } else + *dst++ = *src; + src++; + } + + return (dst - outbuf); +} + +gsize +hdlc_unescape (const char *inbuf, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len, + gboolean *escaping) +{ + size_t i, outsize; + + g_return_val_if_fail (inbuf_len > 0, 0); + g_return_val_if_fail (outbuf_len >= inbuf_len, 0); + g_return_val_if_fail (escaping != NULL, 0); + + for (i = 0, outsize = 0; i < inbuf_len; i++) { + if (*escaping) { + outbuf[outsize++] = inbuf[i] ^ DIAG_ESC_MASK; + *escaping = FALSE; + } else if (inbuf[i] == DIAG_ESC_CHAR) + *escaping = TRUE; + else + outbuf[outsize++] = inbuf[i]; + + /* About to overrun output buffer size */ + if (outsize >= outbuf_len) + return 0; + } + + return outsize; +} + +/** + * hdlc_encapsulate_buffer: + * @inbuf: data buffer to encapsulate + * @cmd_len: size of the data contained in @inbuf + * @inbuf_len: total size of @inbuf itself (not just the data) + * @crc_seed: if non-zero, CRC-16 seed to use; if 0, uses standard 0xFFFF + * @add_trailer: if %TRUE, adds trailing 0x7E + * @escape_all_ctrl: if %TRUE, escapes all control characters instead of only + * special HDLC escape characters 0x7D and 0x7E + * @outbuf: buffer in which to put the encapsulated data + * @outbuf_len: total size of @outbuf + * + * Escapes and CRCs given data using HDLC-style mechanisms, and optionally adds + * the trailing control character that denotes the end of the HDLC frame. + * + * Returns: size of the encapsulated data writted to @outbuf. + **/ +gsize +hdlc_encapsulate_buffer (char *inbuf, + gsize cmd_len, + gsize inbuf_len, + guint16 crc_seed, + gboolean add_trailer, + gboolean escape_all_ctrl, + char *outbuf, + gsize outbuf_len) +{ + guint16 crc; + gsize escaped_len; + + g_return_val_if_fail (inbuf != NULL, 0); + g_return_val_if_fail (cmd_len >= 1, 0); + g_return_val_if_fail (inbuf_len >= cmd_len + 2, 0); /* space for CRC */ + g_return_val_if_fail (outbuf != NULL, 0); + + /* Add the CRC */ + crc = crc16 (inbuf, cmd_len, crc_seed ? crc_seed : 0xFFFF); + inbuf[cmd_len++] = crc & 0xFF; + inbuf[cmd_len++] = (crc >> 8) & 0xFF; + + escaped_len = hdlc_escape (inbuf, cmd_len, escape_all_ctrl, outbuf, outbuf_len); + g_return_val_if_fail (outbuf_len > escaped_len, 0); + + if (add_trailer) + outbuf[escaped_len++] = DIAG_CONTROL_CHAR; + + return escaped_len; +} + +#define AT_WMC_PREFIX "AT*WMC=" + +/** + * uml290_wmc_encapsulate: + * @inbuf: data buffer to encapsulate + * @cmd_len: size of the data contained in @inbuf + * @inbuf_len: total size of @inbuf itself (not just the data) + * @outbuf: buffer in which to put the encapsulated data + * @outbuf_len: total size of @outbuf + * + * Escapes and CRCs given data using HDLC-style mechanisms with UML290 specific + * quirks. + * + * Returns: size of the encapsulated data writted to @outbuf. + */ +gsize +uml290_wmc_encapsulate (char *inbuf, + gsize cmd_len, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len) +{ + gsize encap_len; + gsize estimated_out_len; + + g_return_val_if_fail (inbuf != NULL, 0); + g_return_val_if_fail (cmd_len >= 1, 0); + g_return_val_if_fail (inbuf_len >= cmd_len + 2, 0); /* space for CRC */ + g_return_val_if_fail (outbuf != NULL, 0); + + estimated_out_len = inbuf_len + strlen (AT_WMC_PREFIX); + estimated_out_len += 3; /* CRC + trailer */ + estimated_out_len += cmd_len * 1.3; /* escaping */ + g_return_val_if_fail (outbuf_len > estimated_out_len, 0); + + memcpy (outbuf, AT_WMC_PREFIX, strlen (AT_WMC_PREFIX)); + + encap_len = hdlc_encapsulate_buffer (inbuf, cmd_len, inbuf_len, 0xAAFE, + FALSE, TRUE, + outbuf + strlen (AT_WMC_PREFIX), + outbuf_len); + if (encap_len > 0) { + encap_len += strlen (AT_WMC_PREFIX); + outbuf[encap_len++] = 0x0D; /* trailer */ + } + + return encap_len; +} + +/** + * hdlc_decapsulate_buffer: + * @inbuf: buffer in which to look for an HDLC frame + * @inbuf_len: length of valid data in @inbuf + * @outbuf: buffer in which to put decapsulated data from the HDLC frame + * @outbuf_len: max size of @outbuf + * @out_decap_len: on success, size of the decapsulated data + * @out_used: on either success or failure, amount of data used; caller should + * discard this much data from @inbuf before the next call to this function + * @out_need_more: when TRUE, indicates that more data is required before + * a determination about a valid HDLC frame can be made; caller should add + * more data to @inbuf before calling this function again. + * + * Attempts to retrieve, unescape, and CRC-check an HDLC frame from the given + * buffer. + * + * Returns: FALSE on error (packet was invalid or malformed, or the CRC check + * failed, etc) and places number of bytes to discard from @inbuf in @out_used. + * When TRUE, either more data is required (in which case @out_need_more will + * be TRUE), or a data packet was successfully retrieved from @inbuf and the + * decapsulated packet of length @out_decap_len was placed into @outbuf. In + * all cases the caller should advance the buffer by the number of bytes + * returned in @out_used before calling this function again. + **/ +gboolean +hdlc_decapsulate_buffer (const char *inbuf, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len, + gsize *out_decap_len, + gsize *out_used, + gboolean *out_need_more) +{ + gboolean escaping = FALSE; + gsize i, pkt_len = 0, unesc_len; + guint16 crc, pkt_crc; + + g_return_val_if_fail (inbuf != NULL, FALSE); + g_return_val_if_fail (outbuf != NULL, FALSE); + g_return_val_if_fail (outbuf_len > 0, FALSE); + g_return_val_if_fail (out_decap_len != NULL, FALSE); + g_return_val_if_fail (out_used != NULL, FALSE); + g_return_val_if_fail (out_need_more != NULL, FALSE); + + *out_decap_len = 0; + *out_used = 0; + *out_need_more = FALSE; + + if (inbuf_len < 4) { + *out_need_more = TRUE; + return TRUE; + } + + /* Find the async control character */ + for (i = 0; i < inbuf_len; i++) { + if (inbuf[i] == DIAG_CONTROL_CHAR) { + /* If the control character shows up in a position before a valid + * QCDM packet length (4), the packet is malformed. + */ + if (i < 3) { + /* Tell the caller to advance the buffer past the control char */ + *out_used = i + 1; + return FALSE; + } + + pkt_len = i; + break; + } + } + + /* No control char yet, need more data */ + if (!pkt_len) { + *out_need_more = TRUE; + return TRUE; + } + + /* Unescape first; note that pkt_len */ + unesc_len = hdlc_unescape (inbuf, pkt_len, outbuf, outbuf_len, &escaping); + if (!unesc_len) { + /* Tell the caller to advance the buffer past the control char */ + *out_used = pkt_len + 1; + return FALSE; + } + + if (escaping) { + *out_need_more = TRUE; + return TRUE; + } + + /* Check the CRC of the packet's data */ + crc = crc16 (outbuf, unesc_len - 2, 0); + pkt_crc = outbuf[unesc_len - 2] & 0xFF; + pkt_crc |= (outbuf[unesc_len - 1] & 0xFF) << 8; + if (crc != pkt_crc) { + *out_used = pkt_len + 1; /* packet + CRC + 0x7E */ + return FALSE; + } + + *out_used = pkt_len + 1; /* packet + CRC + 0x7E */ + *out_decap_len = unesc_len - 2; /* decap_len should not include the CRC */ + return TRUE; +} + diff --git a/libwmc/src/utils.h b/libwmc/src/utils.h new file mode 100644 index 00000000..1f2a7c83 --- /dev/null +++ b/libwmc/src/utils.h @@ -0,0 +1,64 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2011 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef UTILS_H +#define UTILS_H + +#include <glib.h> + +#define DIAG_CONTROL_CHAR 0x7E +#define DIAG_TRAILER_LEN 3 + +guint16 crc16 (const char *buffer, gsize len, guint16 seed); + +gsize hdlc_escape (const char *inbuf, + gsize inbuf_len, + gboolean escape_all_ctrl, + char *outbuf, + gsize outbuf_len); + +gsize hdlc_unescape (const char *inbuf, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len, + gboolean *escaping); + +gsize hdlc_encapsulate_buffer (char *inbuf, + gsize cmd_len, + gsize inbuf_len, + guint16 crc_seed, + gboolean add_trailer, + gboolean escape_all_ctrl, + char *outbuf, + gsize outbuf_len); + +gsize uml290_wmc_encapsulate (char *inbuf, + gsize cmd_len, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len); + +gboolean hdlc_decapsulate_buffer (const char *inbuf, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len, + gsize *out_decap_len, + gsize *out_used, + gboolean *out_need_more); + +#endif /* UTILS_H */ + diff --git a/libwmc/tests/Makefile.am b/libwmc/tests/Makefile.am new file mode 100644 index 00000000..8b5e140b --- /dev/null +++ b/libwmc/tests/Makefile.am @@ -0,0 +1,28 @@ +INCLUDES = \ + -I$(top_srcdir)/libwmc/src + +noinst_PROGRAMS = test-wmc + +test_wmc_SOURCES = \ + test-wmc-crc.c \ + test-wmc-crc.h \ + test-wmc-escaping.c \ + test-wmc-escaping.h \ + test-wmc-utils.c \ + test-wmc-utils.h \ + test-wmc.c + +test_wmc_CPPFLAGS = \ + $(MM_CFLAGS) + +test_wmc_LDADD = \ + $(top_builddir)/libwmc/src/libwmc.la \ + $(MM_LIBS) + +if WITH_TESTS + +check-local: test-wmc + $(abs_builddir)/test-wmc + +endif + diff --git a/libwmc/tests/test-wmc-crc.c b/libwmc/tests/test-wmc-crc.c new file mode 100644 index 00000000..a767481d --- /dev/null +++ b/libwmc/tests/test-wmc-crc.c @@ -0,0 +1,65 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <glib.h> +#include <string.h> + +#include "test-wmc-crc.h" +#include "utils.h" + +void +test_crc16_2 (void *f, void *data) +{ + static const char buf[] = { + 0x26, 0xb2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00 + }; + guint16 crc; + guint16 expected = 0x6D69; + + /* CRC check */ + crc = crc16 (buf, sizeof (buf), 0); + g_assert (crc == expected); +} + +void +test_crc16_1 (void *f, void *data) +{ + static const char buf[] = { + 0x4b, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, + 0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0x3f, + 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff + }; + guint16 crc; + guint16 expected = 0x097A; + + /* CRC check */ + crc = crc16 (buf, sizeof (buf), 0); + g_assert (crc == expected); +} + diff --git a/libwmc/tests/test-wmc-crc.h b/libwmc/tests/test-wmc-crc.h new file mode 100644 index 00000000..4ce2871b --- /dev/null +++ b/libwmc/tests/test-wmc-crc.h @@ -0,0 +1,25 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef TEST_WMC_CRC_H +#define TEST_WMC_CRC_H + +void test_crc16_2 (void *f, void *data); +void test_crc16_1 (void *f, void *data); + +#endif /* TEST_WMC_CRC_H */ + diff --git a/libwmc/tests/test-wmc-escaping.c b/libwmc/tests/test-wmc-escaping.c new file mode 100644 index 00000000..a49c04e4 --- /dev/null +++ b/libwmc/tests/test-wmc-escaping.c @@ -0,0 +1,124 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <glib.h> +#include <string.h> + +#include "test-wmc-escaping.h" +#include "utils.h" + +static const char data1[] = { + 0x70, 0x68, 0x6f, 0x6e, 0x65, 0x66, 0x61, 0x69, 0x6c, 0x75, 0x72, 0x65, + 0x0a, 0x6e, 0x6f, 0x63, 0x6f, 0x6e, 0x6e, 0x65, 0x63, 0x74, 0x69, 0x6f, + 0x6e, 0x74, 0x6f, 0x70, 0x68, 0x6f, 0x6e, 0x65, 0x0a, 0x70, 0x68, 0x6f, + 0x6e, 0x7e, 0x7e, 0x7e, 0x7d, 0x7d, 0x7e, 0x7d, 0x7e, 0x7d, 0x7e, 0x6e, + 0x6b, 0x72, 0x65, 0x73, 0x65, 0x72, 0x76, 0x65, 0x64, 0x0a, 0x6f, 0x70, + 0x65, 0x72, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x6e, 0x6f, 0x74, 0x61, 0x6c, + 0x6c, 0x6f, 0x77, 0x65, 0x64, 0x0a, 0x6f, 0x70, 0x65, 0x72, 0x61, 0x74, + 0x69, 0x6f, 0x6e, 0x6e, 0x6f, 0x74, 0x73, 0x75, 0x70, 0x70, 0x6f, 0x72, + 0x74, 0x65, 0x64, 0x0a, 0x70, 0x68, 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, + 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x0a, 0x70, 0x68, 0x66, + 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, + 0x65, 0x64, 0x0a, 0x70, 0x68, 0x66, 0x73, 0x69, 0x6d, 0x70, 0x75, 0x6b, + 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x0a, 0x73, 0x69, 0x6d, + 0x6e, 0x6f, 0x74, 0x69, 0x6e, 0x73, 0x65, 0x72, 0x74, 0x65, 0x64, 0x0a, + 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, + 0x65, 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x70, 0x75, 0x6b, 0x72, 0x65, 0x71, + 0x75, 0x69, 0x72, 0x65, 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x66, 0x61, 0x69, + 0x6c, 0x75, 0x72, 0x65, 0x0a, 0x73, 0x69, 0x6d, 0x62, 0x75, 0x73, 0x79, + 0x0a, 0x73, 0x69, 0x6d, 0x77, 0x72, 0x6f, 0x6e, 0x67, 0x0a, 0x69, 0x6e, + 0x63, 0x6f, 0x72, 0x72, 0x65, 0x63, 0x74, 0x70, 0x61, 0x73, 0x73, 0x77, + 0x6f, 0x72, 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, 0x32, 0x72, + 0x65, 0x71, 0x75, 0x69 +}; + +static const char expected1[] = { + 0x70, 0x68, 0x6f, 0x6e, 0x65, 0x66, 0x61, 0x69, 0x6c, 0x75, 0x72, 0x65, + 0x0a, 0x6e, 0x6f, 0x63, 0x6f, 0x6e, 0x6e, 0x65, 0x63, 0x74, 0x69, 0x6f, + 0x6e, 0x74, 0x6f, 0x70, 0x68, 0x6f, 0x6e, 0x65, 0x0a, 0x70, 0x68, 0x6f, + 0x6e, 0x7d, 0x5e, 0x7d, 0x5e, 0x7d, 0x5e, 0x7d, 0x5d, 0x7d, 0x5d, 0x7d, + 0x5e, 0x7d, 0x5d, 0x7d, 0x5e, 0x7d, 0x5d, 0x7d, 0x5e, 0x6e, 0x6b, 0x72, + 0x65, 0x73, 0x65, 0x72, 0x76, 0x65, 0x64, 0x0a, 0x6f, 0x70, 0x65, 0x72, + 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x6e, 0x6f, 0x74, 0x61, 0x6c, 0x6c, 0x6f, + 0x77, 0x65, 0x64, 0x0a, 0x6f, 0x70, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6f, + 0x6e, 0x6e, 0x6f, 0x74, 0x73, 0x75, 0x70, 0x70, 0x6f, 0x72, 0x74, 0x65, + 0x64, 0x0a, 0x70, 0x68, 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, 0x72, 0x65, + 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x0a, 0x70, 0x68, 0x66, 0x73, 0x69, + 0x6d, 0x70, 0x69, 0x6e, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, + 0x0a, 0x70, 0x68, 0x66, 0x73, 0x69, 0x6d, 0x70, 0x75, 0x6b, 0x72, 0x65, + 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x6e, 0x6f, + 0x74, 0x69, 0x6e, 0x73, 0x65, 0x72, 0x74, 0x65, 0x64, 0x0a, 0x73, 0x69, + 0x6d, 0x70, 0x69, 0x6e, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, + 0x0a, 0x73, 0x69, 0x6d, 0x70, 0x75, 0x6b, 0x72, 0x65, 0x71, 0x75, 0x69, + 0x72, 0x65, 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x66, 0x61, 0x69, 0x6c, 0x75, + 0x72, 0x65, 0x0a, 0x73, 0x69, 0x6d, 0x62, 0x75, 0x73, 0x79, 0x0a, 0x73, + 0x69, 0x6d, 0x77, 0x72, 0x6f, 0x6e, 0x67, 0x0a, 0x69, 0x6e, 0x63, 0x6f, + 0x72, 0x72, 0x65, 0x63, 0x74, 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, + 0x64, 0x0a, 0x73, 0x69, 0x6d, 0x70, 0x69, 0x6e, 0x32, 0x72, 0x65, 0x71, + 0x75, 0x69 +}; + +void +test_escape1 (void *f, void *data) +{ + char escaped[1024]; + gsize len; + + /* Ensure that escaping in general works */ + len = hdlc_escape (data1, sizeof (data1), FALSE, escaped, sizeof (escaped)); + g_assert (len == 266); + g_assert (len == sizeof (expected1)); + g_assert (memcmp (escaped, expected1, len) == 0); +} + +static const char data2[] = { + 0x4b, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, + 0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0x3f, + 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff +}; + +void +test_escape2 (void *f, void *data) +{ + char escaped[1024]; + gsize len; + + /* Ensure that escaping data that doesn't need escaping works */ + len = hdlc_escape (data2, sizeof (data2), FALSE, escaped, sizeof (escaped)); + g_assert (len == sizeof (data2)); + g_assert (memcmp (escaped, data2, len) == 0); +} + +void +test_escape_unescape (void *f, void *data) +{ + char escaped[512]; + char unescaped[512]; + gsize len, unlen; + gboolean escaping = FALSE; + + /* Ensure that escaping data that needs escaping, and then unescaping it, + * produces the exact same data as was originally escaped. + */ + len = hdlc_escape (data1, sizeof (data1), FALSE, escaped, sizeof (escaped)); + unlen = hdlc_unescape (escaped, len, unescaped, sizeof (unescaped), &escaping); + + g_assert (unlen == sizeof (data1)); + g_assert (memcmp (unescaped, data1, unlen) == 0); +} + diff --git a/libwmc/tests/test-wmc-escaping.h b/libwmc/tests/test-wmc-escaping.h new file mode 100644 index 00000000..7b5c08c4 --- /dev/null +++ b/libwmc/tests/test-wmc-escaping.h @@ -0,0 +1,26 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef TEST_WMC_ESCAPING_H +#define TEST_WMC_ESCAPING_H + +void test_escape1 (void *f, void *data); +void test_escape2 (void *f, void *data); +void test_escape_unescape (void *f, void *data); + +#endif /* TEST_WMC_ESCAPING_H */ + diff --git a/libwmc/tests/test-wmc-utils.c b/libwmc/tests/test-wmc-utils.c new file mode 100644 index 00000000..3046e33d --- /dev/null +++ b/libwmc/tests/test-wmc-utils.c @@ -0,0 +1,107 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <glib.h> +#include <string.h> + +#include "test-wmc-utils.h" +#include "utils.h" + +static const char decap_inbuf[] = { + 0x40, 0x03, 0x00, 0x01, 0x00, 0x19, 0xf0, 0x00, 0x16, 0x00, 0x21, 0x00, + 0x1c, 0x00, 0xd8, 0x00, 0x3f, 0x00, 0x56, 0x01, 0x3f, 0x00, 0x15, 0x00, + 0x1a, 0x00, 0x11, 0x01, 0x3f, 0x00, 0x92, 0x01, 0x3f, 0x00, 0x39, 0x00, + 0x3f, 0x00, 0x95, 0x01, 0x3f, 0x00, 0x12, 0x00, 0x3f, 0x00, 0x23, 0x01, + 0x3f, 0x00, 0x66, 0x00, 0x3f, 0x00, 0x0b, 0x01, 0x3f, 0x00, 0xae, 0x00, + 0x3f, 0x00, 0x02, 0x01, 0x3f, 0x00, 0xa8, 0x00, 0x3f, 0x00, 0x50, 0x01, + 0x3f, 0x00, 0xf8, 0x01, 0x3f, 0x00, 0x57, 0x00, 0x3f, 0x00, 0x7d, 0x5e, + 0x00, 0x3f, 0x00, 0x93, 0x00, 0x3f, 0x00, 0xbd, 0x00, 0x3f, 0x00, 0x77, + 0x01, 0x3f, 0x00, 0xb7, 0x00, 0x3f, 0x00, 0xab, 0x00, 0x3f, 0x00, 0x33, + 0x00, 0x3f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x13, + 0x13, 0x50, 0x1f, 0x00, 0x00, 0xff, 0xff, 0x00, 0xaa, 0x19, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xb1, 0xc4, 0x7d, 0x5e, + 0x7d, 0x5e, 0x7d, 0x5d, 0x5d, 0x04, 0x58, 0x1b, 0x5b, 0x1b, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x65, 0x69, 0x7e +}; + +void +test_utils_decapsulate_buffer (void *f, void *data) +{ + gboolean success; + char outbuf[512]; + gsize decap_len = 0; + gsize used = 0; + gboolean more = FALSE; + + success = hdlc_decapsulate_buffer (decap_inbuf, sizeof (decap_inbuf), + outbuf, sizeof (outbuf), + &decap_len, &used, &more); + g_assert (success); + g_assert (decap_len == 214); + g_assert (used == 221); + g_assert (more == FALSE); +} + + +static const char encap_outbuf[] = { + 0x4b, 0x05, 0x08, 0x00, 0x01, 0xdd, 0x7e +}; + +void +test_utils_encapsulate_buffer (void *f, void *data) +{ + char cmdbuf[10]; + char outbuf[512]; + gsize encap_len = 0; + + cmdbuf[0] = 0x4B; /* DIAG_CMD_SUBSYS */ + cmdbuf[1] = 0x05; /* DIAG_SUBSYS_HDR */ + cmdbuf[2] = 0x08; /* first byte of DIAG_SUBSYS_HDR_STATE_INFO in LE */ + cmdbuf[3] = 0x00; /* second byte of DIAG_SUBSYS_HDR_STATE_INFO in LE */ + + encap_len = hdlc_encapsulate_buffer (cmdbuf, 4, sizeof (cmdbuf), + 0, TRUE, FALSE, + &outbuf[0], sizeof (outbuf)); + g_assert (encap_len == sizeof (encap_outbuf)); + g_assert (memcmp (outbuf, encap_outbuf, encap_len) == 0); +} + +static const char cns_inbuf[] = { + 0x00, 0x0a, 0x6b, 0x74, 0x00, 0x00, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x7e +}; + +void +test_utils_decapsulate_sierra_cns (void *f, void *data) +{ + gboolean success; + char outbuf[512]; + gsize decap_len = 0; + gsize used = 0; + gboolean more = FALSE; + + success = hdlc_decapsulate_buffer (cns_inbuf, sizeof (cns_inbuf), + outbuf, sizeof (outbuf), + &decap_len, &used, &more); + g_assert (success == FALSE); +} + diff --git a/libwmc/tests/test-wmc-utils.h b/libwmc/tests/test-wmc-utils.h new file mode 100644 index 00000000..ac55dc8b --- /dev/null +++ b/libwmc/tests/test-wmc-utils.h @@ -0,0 +1,28 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef TEST_WMC_UTILS_H +#define TEST_WMC_UTILS_H + +void test_utils_decapsulate_buffer (void *f, void *data); + +void test_utils_encapsulate_buffer (void *f, void *data); + +void test_utils_decapsulate_sierra_cns (void *f, void *data); + +#endif /* TEST_WMC_UTILS_H */ + diff --git a/libwmc/tests/test-wmc.c b/libwmc/tests/test-wmc.c new file mode 100644 index 00000000..6a531800 --- /dev/null +++ b/libwmc/tests/test-wmc.c @@ -0,0 +1,54 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * Copyright (C) 2010 Red Hat, Inc. + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <glib.h> +#include <string.h> + +#include "test-wmc-crc.h" +#include "test-wmc-escaping.h" +#include "test-wmc-utils.h" + +#if GLIB_CHECK_VERSION(2,25,12) +typedef GTestFixtureFunc TCFunc; +#else +typedef void (*TCFunc)(void); +#endif + +#define TESTCASE(t, d) g_test_create_case (#t, 0, d, NULL, (TCFunc) t, NULL) + +int main (int argc, char **argv) +{ + GTestSuite *suite; + gint result; + + g_test_init (&argc, &argv, NULL); + + suite = g_test_get_root (); + g_test_suite_add (suite, TESTCASE (test_crc16_1, NULL)); + g_test_suite_add (suite, TESTCASE (test_crc16_2, NULL)); + g_test_suite_add (suite, TESTCASE (test_escape1, NULL)); + g_test_suite_add (suite, TESTCASE (test_escape2, NULL)); + g_test_suite_add (suite, TESTCASE (test_escape_unescape, NULL)); + g_test_suite_add (suite, TESTCASE (test_utils_decapsulate_buffer, NULL)); + g_test_suite_add (suite, TESTCASE (test_utils_encapsulate_buffer, NULL)); + g_test_suite_add (suite, TESTCASE (test_utils_decapsulate_sierra_cns, NULL)); + + result = g_test_run (); + + return result; +} + diff --git a/uml290.txt b/libwmc/uml290.txt index 59b65323..5a6113a6 100644 --- a/uml290.txt +++ b/libwmc/uml290.txt @@ -80,31 +80,74 @@ The protocol is a request/response style protocol though unsolicited responses are sometimes sent from the modem to the host. There does not appear to be any sequence numbering in either the request or response packets. WMC packets always begin with the frame start marker (0xC8). The second byte is the command -number. The frame ends with a three-byte trailer including a CRC-16 and a -standard HDLC/PPP frame terminator (0x7E), though this terminator is missing in -some cases as described below. Thus a normal WMC packet looks like this: +number, followed by the frame's data. The frame ends with a three-byte trailer +including a CRC-16 and a frame termination marker which differs between devices. +Most older devices use the standard HDLC/PPP frame termination marker (0x7E), +while some others (UML290) use a different termination marker as described +below. Thus a normal WMC packet looks like this: 0xC8 <command number> <data> <CRC-16> 0x7E -The entire frame (exclusive of the 0x7E frame terminator) is escaped using -standard HDLC/PPP escaping mechanisms to ensure that the bytes 0x7E and 0x7D -never appear in the packet. +The entire frame (exclusive of the termination marker) is escaped using standard +HDLC/PPP escaping mechanisms to ensure that the bytes 0x7E and 0x7D never appear +in the packet. Some devices (UML290) escape more than the standard HDLC escape +characters. + +Frames can span multiple USB packets. This behavior has been observed with the +PC5740 in various responses, in which case the frame is simply split up between +USB packets. It has also been observed with some UML290 requests, where it +appears that in addition to splitting the frame, each segment after the first +is prefixed with 0x20. + +For example, a split response from a PC5740: + +* c8 06 0f 0f 0f 0f 0f 0f 0f 0f 0f 0f 00 00 00 00 ................ + ... + 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ............... + +* 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ + ... + 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ............... + +* 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ + ... + 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ............... + +* 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ + ... + 00 00 00 01 .... + + +and an split request from a UML290: + +* c8 56 86 02 00 00 00 00 00 00 39 30 30 30 38 30 .V........900080 + ... + 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .............. + +* 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ............... + ... + 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ + +* 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ............... + ... + 00 00 00 00 00 00 00 00 00 00 5b 1c 0d ..........[.. + Requests --------------- Requests are usually short, often only 4 or 5 bytes long, including the frame -start marker (0xC8), the command number, the CRC, and the frame termination -marker. Requests always receive a response from the modem containing the same -command number. +start marker (0xC8), the command number, the 16-bit CRC, and the frame termination +marker. Requests almost always receive a response from the modem containing the +same command number. The UML290 uses different "AT"-style framing of requests, prefixing the request with "AT*WMC=" and using a frame termination marker of 0x0D instead of the standard 0x7E. The UML290 also uses a different CRC-16 initial seed of 0xAAFE instead of the standard 0xFFFF used on other devices and with HDLC framing in general. For added lolz the UML290 HDLC-escapes all control -characters in the request instead of only the standard 0x7D and 0x7E characters +characters in the request in addition to the standard 0x7D and 0x7E characters escaped in HDLC. Thus a normal WMC request (from a PC5740) looks like this: |