diff options
| -rw-r--r-- | util/nvmutil/nvmutil.c | 126 | ||||
| -rw-r--r-- | util/spkmodem_decode/spkmodem-decode.c | 355 |
2 files changed, 274 insertions, 207 deletions
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c index b718ac6e..da6336aa 100644 --- a/util/nvmutil/nvmutil.c +++ b/util/nvmutil/nvmutil.c @@ -47,9 +47,6 @@ * TODO: bound checks for files per-command, e.g. only * first 6 bytes for CMD_SETMAC * - * TODO: clean up the do_rw function: make PSCHREIB and - * so on clearer, probably just define them inline and - * validate them inline (no define). * TODO: in command sanitizer: verify that each given * entry corresponds to the correct function, in the * pointer (this check is currently missing) @@ -85,10 +82,6 @@ * TODO: also document the layout of Intel GbE files, so * that wily individuals can easily expand the * featureset of nvmutil. - * TODO: remove some clever code, e.g.: - * rw_type == PLESEN << 2 - * make stuff like that clearer. - * ditto the invert copy/swap trick * TODO: write a manpage * TODO: simplify the command sanitization, implement more * of it as build time checks, e.g. static asserts. @@ -441,10 +434,10 @@ static const char *argv0; #define ARGC_4 4 enum { - LESEN, - PLESEN, - SCHREIB, - PSCHREIB + IO_READ, + IO_WRITE, + IO_PREAD, + IO_PWRITE }; /* @@ -567,6 +560,10 @@ static size_t cmd_index = CMD_NULL; typedef char assert_argc3[(ARGC_3==3)?1:-1]; typedef char assert_argc4[(ARGC_4==4)?1:-1]; +typedef char assert_read[(IO_READ==0)?1:-1]; +typedef char assert_write[(IO_WRITE==1)?1:-1]; +typedef char assert_pread[(IO_PREAD==2)?1:-1]; +typedef char assert_pwrite[(IO_PWRITE==3)?1:-1]; static int use_prng = 0; @@ -736,9 +733,6 @@ sanitize_command_index(size_t c) if (command[c].flags != O_RDONLY && command[c].flags != O_RDWR) err(EINVAL, "invalid cmd.flags setting"); - - if (!((!LESEN) && (PLESEN == 1) && (SCHREIB == 2) && (PSCHREIB == 3))) - err(EINVAL, "rw type integers are the wrong values"); } static void @@ -906,7 +900,7 @@ read_gbe_file(void) for (p = 0; p < 2; p++) { if (do_read[p]) - rw_gbe_file_part(p, PLESEN, "pread"); + rw_gbe_file_part(p, IO_PREAD, "pread"); } } @@ -1133,20 +1127,12 @@ rhex(void) static size_t n = 0; static uint8_t rnum[12]; - if (use_prng) { - /* - * On very old Unix systems that - * lack /dev/random and /dev/urandom - */ + if (use_prng) return fallback_rand(); - } - - if (urandom_fd < 0) - err(ECANCELED, "Your operating system has no /dev/[u]random"); if (!n) { n = sizeof(rnum); - if (rw_file_exact(urandom_fd, rnum, n, 0, LESEN) == -1) + if (rw_file_exact(urandom_fd, rnum, n, 0, IO_READ) == -1) err(errno, "Randomisation failed"); } @@ -1305,7 +1291,7 @@ gbe_cat_buf(uint8_t *b) while (1) { rval = rw_file_exact(STDOUT_FILENO, b, - GBE_PART_SIZE, 0, SCHREIB); + GBE_PART_SIZE, 0, IO_WRITE); if (rval >= 0) { /* @@ -1346,7 +1332,7 @@ write_gbe_file(void) if (update_checksum) set_checksum(partnum); - rw_gbe_file_part(partnum, PSCHREIB, "pwrite"); + rw_gbe_file_part(partnum, IO_PWRITE, "pwrite"); } } @@ -1470,7 +1456,7 @@ rw_gbe_file_part(size_t p, int rw_type, uint8_t *mem_offset; - if (rw_type == SCHREIB || rw_type == PSCHREIB) + if (rw_type == IO_WRITE || rw_type == IO_PWRITE) invert = 0; /* @@ -1559,8 +1545,8 @@ gbe_x_offset(size_t p, const char *f_op, const char *d_type, * write() to ignore the current file offset and * write at EOF, which means that our use of * lseek in prw() does not guarantee writing at - * a specified offset. So if using PSCHREIB or - * PLESEN, make sure not to pass a file descriptor + * a specified offset. So if using IO_PWRITE or + * IO_PREAD, make sure not to pass a file descriptor * with the O_APPEND flag. Alternatively, modify * do_rw() to directly use pwrite() and pread() * instead of prw(). @@ -1572,19 +1558,26 @@ rw_file_exact(int fd, uint8_t *mem, size_t len, ssize_t rv; size_t rc; - if (fd < 0 || !len || len > (size_t)SSIZE_MAX) { + if (fd < 0 || !len || len > (size_t)SSIZE_MAX + || (unsigned int)rw_type > IO_PWRITE) { errno = EIO; return -1; } - for (rc = 0, rv = 0; rc < len; rc += (size_t)rv) { - if ((rv = rw_file_once(fd, mem, len, off, rw_type, rc)) == -1) + for (rc = 0, rv = 0; rc < len; ) { + if ((rv = rw_file_once(fd, mem, len, off, rw_type, rc)) <= 0) return -1; + + rc += (size_t)rv; } return rc; } +/* + * May not return all requested bytes (len). + * Use rw_file_exact for guaranteed length. + */ static ssize_t rw_file_once(int fd, uint8_t *mem, size_t len, off_t off, int rw_type, size_t rc) @@ -1594,61 +1587,46 @@ rw_file_once(int fd, uint8_t *mem, size_t len, size_t max_retries = 10; read_again: + if ((unsigned int)rw_type > IO_PWRITE) + goto err_rw_file_once; + rv = do_rw(fd, mem + rc, len - rc, off + rc, rw_type); - if (rv < 0 && errno == EINTR) { + if (rv < 0 && errno == EINTR) goto read_again; - } else if (rv < 0) { - errno = EIO; - return -1; - } - /* - * Theoretical bug: if a buggy libc returned - * a size larger than SSIZE_MAX, the cast may - * cause an overflow. Specifications guarantee - * this won't happen, but spec != implementation - */ - if ((size_t)rv > SSIZE_MAX) { - errno = EIO; + if (rv < 0) return -1; - /* we will not tolerate your buggy libc */ - } - if ((size_t)rv > (len - rc) /* Prevent overflow */ - || rv == 0) { /* Prevent infinite 0-byte loop */ - if (rv == 0) { - /* - * Fault tolerance against infinite - * zero-byte loop: re-try a finite - * number of times. This mitigates - * otherwise OK but slow filesystems - * e.g. NFS or slow media. - */ - if (retries_on_zero++ < max_retries) - goto read_again; - } - errno = EIO; - return -1; - } + if ((size_t)rv > SSIZE_MAX /* theoretical buggy libc */ + || (size_t)rv > (len - rc))/* don't overflow */ + goto err_rw_file_once; + + if (rv != 0) + return rv; + + if (retries_on_zero++ < max_retries) + goto read_again; - return rv; +err_rw_file_once: + errno = EIO; + return -1; } static ssize_t do_rw(int fd, uint8_t *mem, size_t len, off_t off, int rw_type) { - if (rw_type == LESEN || rw_type == PLESEN << 2) + if (rw_type == IO_READ) return read(fd, mem, len); - if (rw_type == SCHREIB || rw_type == PSCHREIB << 2) + if (rw_type == IO_WRITE) return write(fd, mem, len); - if (rw_type == PLESEN || rw_type == PSCHREIB) + if (rw_type == IO_PREAD || rw_type == IO_PWRITE) return prw(fd, mem, len, off, rw_type); - errno = EINVAL; + errno = EIO; return -1; } @@ -1668,6 +1646,14 @@ prw(int fd, void *mem, size_t nrw, off_t off_orig; ssize_t r; int saved_errno; + int prw_type; + + prw_type = rw_type ^ IO_PREAD; + + if ((unsigned int)prw_type > IO_WRITE) { + errno = EIO; + return -1; + } if ((off_orig = lseek_eintr(fd, (off_t)0, SEEK_CUR)) == (off_t)-1) return -1; @@ -1675,7 +1661,7 @@ prw(int fd, void *mem, size_t nrw, return -1; do { - r = do_rw(fd, mem, nrw, off, rw_type << 2); + r = do_rw(fd, mem, nrw, off, prw_type); } while (r < 0 && errno == EINTR); saved_errno = errno; diff --git a/util/spkmodem_decode/spkmodem-decode.c b/util/spkmodem_decode/spkmodem-decode.c index 0c98faf6..3b3b33f8 100644 --- a/util/spkmodem_decode/spkmodem-decode.c +++ b/util/spkmodem_decode/spkmodem-decode.c @@ -63,6 +63,7 @@ #endif #include <errno.h> +#include <limits.h> #include <stdio.h> #include <stdarg.h> #include <stdlib.h> @@ -143,7 +144,7 @@ * Convert tone frequency ranges into pulse counts within the * sliding analysis window. * - * pulse_count ≈ tone_frequency / FRAME_RATE + * pulse_count = tone_frequency / FRAME_RATE * where FRAME_RATE = SAMPLE_RATE / SAMPLES_PER_FRAME. */ #define FREQ_SEP_MIN ((SEP_TONE_MIN_HZ) / (FRAME_RATE)) @@ -205,34 +206,69 @@ struct decoder_state { int freq_max; int freq_threshold; int learn_frames; + + /* previous sample used for edge detection */ + signed short prev_sample; }; static const char *argv0; +/* + * 16-bit little endian words are read + * continuously. we will swap them, if + * the host cpu is big endian. + */ static int host_is_big_endian(void); + +/* main loop */ static void handle_audio(struct decoder_state *st); + +/* separate tone tolerances */ +static void select_separator_tone(struct decoder_state *st); +static int is_valid_signal(struct decoder_state *st); + +/* output to terminal */ +static int set_ascii_bit(struct decoder_state *st); +static void print_char(struct decoder_state *st); +static void reset_char(struct decoder_state *st); + +/* process samples/frames */ +static void decode_pulse(struct decoder_state *st); +static signed short read_sample(struct decoder_state *st); +static void read_words(struct decoder_state *st); + +/* continually adjust tone */ static void detect_tone(struct decoder_state *st); static int silent_signal(struct decoder_state *st); static void select_low_tone(struct decoder_state *st); -static void collect_separator_tone(struct decoder_state *st); -static int valid_signal(struct decoder_state *st); -static void decode_pulse(struct decoder_state *st); -static signed short read_sample(struct decoder_state *st); -static int set_ascii_bit(struct decoder_state *st); -static void print_char(struct decoder_state *st); + +/* debug */ static void print_stats(struct decoder_state *st); -static void reset_char(struct decoder_state *st); +/* error handling / usage */ static void err(int errval, const char *msg, ...); static void usage(void); static const char *progname(void); +/* portability (old systems) */ int getopt(int, char * const *, const char *); extern char *optarg; extern int optind; extern int opterr; extern int optopt; +#ifndef CHAR_BIT +#define CHAR_BIT 8 +#endif + +typedef char static_assert_char_is_8_bits[(CHAR_BIT == 8) ? 1 : -1]; +typedef char static_assert_char_is_1[(sizeof(char) == 1) ? 1 : -1]; +typedef char static_assert_short[(sizeof(short) == 2) ? 1 : -1]; +typedef char static_assert_int_is_4[(sizeof(int) >= 4) ? 1 : -1]; +typedef char static_assert_twos_complement[ + ((-1 & 3) == 3) ? 1 : -1 +]; + int main(int argc, char **argv) { @@ -297,130 +333,115 @@ handle_audio(struct decoder_state *st) int sample; /* - * If the modem signal disappears for several frames, - * discard the partially assembled character. + * If the modem signal disappears for several (read: 3) + * frames, discard the partially assembled character. */ - if (st->sample_count >= (3 * SAMPLES_PER_FRAME)) + if (st->sample_count >= (3 * SAMPLES_PER_FRAME) || + st->freq_separator <= 0) reset_char(st); - collect_separator_tone(st); - decode_pulse(st); - - if (set_ascii_bit(st) < 0) - print_char(st); - st->sample_count = 0; + + /* process exactly one frame */ for (sample = 0; sample < SAMPLES_PER_FRAME; sample++) decode_pulse(st); + select_separator_tone(st); + + if (set_ascii_bit(st) < 0) + print_char(st); + /* Detect tone per each frame */ detect_tone(st); } /* - * Automatically detect spkmodem tone + * collect separator tone statistics + * (and auto-adjust tolerances) */ static void -detect_tone(struct decoder_state *st) +select_separator_tone(struct decoder_state *st) { - if (st->learn_frames >= LEARN_FRAMES) + int avg; + + if (!is_valid_signal(st)) return; - st->learn_frames++; + st->sep_sum += st->freq_separator; + st->sep_samples++; - if (silent_signal(st)) + if (st->sep_samples != 50) return; - select_low_tone(st); + avg = st->sep_sum / st->sep_samples; - if (st->learn_frames == LEARN_FRAMES) { - st->freq_threshold = - (st->freq_min + st->freq_max) / 2; + st->sep_min = avg - SEP_TOLERANCE_PULSES; + st->sep_max = avg + SEP_TOLERANCE_PULSES; - if (st->debug) - printf("auto threshold: %dHz\n", - st->freq_threshold * FRAME_RATE); - } + /* reset calibration accumulators */ + st->sep_sum = 0; + st->sep_samples = 0; + + if (st->debug) + printf("separator calibrated: %dHz\n", + avg * FRAME_RATE); } /* - * Ignore silence / near silence. - * Both FIR windows will be near zero when no signal exists. + * Verify that the observed pulse densities fall within the + * expected ranges for spkmodem tones. This prevents random noise + * from being misinterpreted as data. */ static int -silent_signal(struct decoder_state *st) +is_valid_signal(struct decoder_state *st) { - return (st->freq_data <= 2 && - st->freq_separator <= 2); + if (st->freq_data <= 0) + return 0; + + if (st->freq_separator < st->sep_min || + st->freq_separator > st->sep_max) + return 0; + + return 1; } /* - * Choose the lowest active tone. - * Separator frames carry tone in the separator window, - * data frames carry tone in the data window. + * Each validated frame contributes one bit of modem data. + * Bits are accumulated MSB-first into the ASCII byte. */ -static void -select_low_tone(struct decoder_state *st) +static int +set_ascii_bit(struct decoder_state *st) { - int f; - - f = st->freq_data; + if (st->debug) + print_stats(st); - if (f <= 0 || (st->freq_separator > 0 && - st->freq_separator < f)) - f = st->freq_separator; + if (!is_valid_signal(st)) + return st->ascii_bit; - if (f <= 0) - return; + if (st->freq_data < st->freq_threshold) + st->ascii |= (1 << st->ascii_bit); - if (f < st->freq_min) - st->freq_min = f; + st->ascii_bit--; - if (f > st->freq_max) - st->freq_max = f; + return st->ascii_bit; } -/* - * collect separator tone statistics - * (and auto-adjust tolerances) - */ static void -collect_separator_tone(struct decoder_state *st) +print_char(struct decoder_state *st) { - int avg; - - if (valid_signal(st)) - return; - - if (st->sep_samples >= 50 && st->freq_separator <= 0) - return; - - st->sep_sum += st->freq_separator; - st->sep_samples++; - - if (st->sep_samples != 50) - return; - - avg = st->sep_sum / st->sep_samples; - - st->sep_min = avg - SEP_TOLERANCE_PULSES; - st->sep_max = avg + SEP_TOLERANCE_PULSES; - if (st->debug) - printf("separator calibrated: %dHz\n", - avg * FRAME_RATE); + printf("<%c,%x>", st->ascii, st->ascii); + else + putchar(st->ascii); + + reset_char(st); } -/* - * Verify that the observed pulse densities fall within the - * expected ranges for spkmodem tones. This prevents random noise - * from being misinterpreted as data. - */ -static int -valid_signal(struct decoder_state *st) +static void +reset_char(struct decoder_state *st) { - return (st->freq_separator > 0 && - st->freq_data > 0); + st->ascii = 0; + st->ascii_bit = 7; } /* @@ -431,9 +452,11 @@ decode_pulse(struct decoder_state *st) { unsigned char old_ring, old_sep; unsigned char new_pulse; + signed short sample; int ringpos; int sep_pos; - signed short sample; + int diff_edge; + int diff_amp; ringpos = st->ringpos; sep_pos = st->sep_pos; @@ -469,18 +492,33 @@ decode_pulse(struct decoder_state *st) sample = read_sample(st); /* - * Convert the waveform sample into a pulse (0 or 1). + * Avoid startup edge. Since + * it's zero at startup, this + * may wrongly produce a pulse + */ + if (st->sample_count == 0) + st->prev_sample = sample; + + /* + * Detect edges instead of amplitude. + * This is more tolerant of weak microphones + * and speaker distortion.. * - * The unsigned comparison creates a small dead zone near zero, - * suppressing small amplitude noise from microphones or - * cheap ADCs. Real PC speaker tones are far outside this - * range, so they still produce clean pulses. + * However, we check both slope edges and + * amplitude, to mitagate noise. */ - if ((unsigned)(sample + THRESHOLD) - > (unsigned)(2 * THRESHOLD)) + diff_amp = sample; + diff_edge = sample - st->prev_sample; + if (diff_edge < 0) + diff_edge = -diff_edge; + if (diff_amp < 0) + diff_amp = -diff_amp; + if (diff_edge > THRESHOLD && + diff_amp > THRESHOLD) new_pulse = 1; else new_pulse = 0; + st->prev_sample = sample; st->pulse[ringpos] = new_pulse; st->freq_separator += new_pulse; @@ -490,11 +528,9 @@ decode_pulse(struct decoder_state *st) * The separator window always stays one frame ahead * of the data window. */ - ringpos++; - if (ringpos >= MAX_SAMPLES) + if (++ringpos >= MAX_SAMPLES) ringpos = 0; - sep_pos++; - if (sep_pos >= MAX_SAMPLES) + if (++sep_pos >= MAX_SAMPLES) sep_pos = 0; st->ringpos = ringpos; @@ -506,25 +542,11 @@ decode_pulse(struct decoder_state *st) static signed short read_sample(struct decoder_state *st) { - size_t n; signed short sample; unsigned short u; - while (st->inpos >= st->inlen) { - - n = fread(st->inbuf, sizeof(st->inbuf[0]), - READ_BUF, stdin); - - if (n == 0) { - if (ferror(stdin)) - err(errno, "stdin read"); - if (feof(stdin)) - exit(EXIT_SUCCESS); - } - - st->inpos = 0; - st->inlen = n; - } + while (st->inpos >= st->inlen) + read_words(st); sample = st->inbuf[st->inpos++]; @@ -538,31 +560,97 @@ read_sample(struct decoder_state *st) return sample; } +static void +read_words(struct decoder_state *st) +{ + size_t n; + + n = fread(st->inbuf, sizeof(st->inbuf[0]), + READ_BUF, stdin); + + if (n != 0) { + st->inpos = 0; + st->inlen = n; + + return; + } + + if (ferror(stdin)) + err(errno, "stdin read"); + if (feof(stdin)) + exit(EXIT_SUCCESS); +} + /* - * Each validated frame contributes one bit of modem data. - * Bits are accumulated MSB-first into the ASCII byte. + * Automatically detect spkmodem tone */ -static int -set_ascii_bit(struct decoder_state *st) +static void +detect_tone(struct decoder_state *st) { + if (st->learn_frames >= LEARN_FRAMES) + return; + + st->learn_frames++; + + if (silent_signal(st)) + return; + + select_low_tone(st); + + if (st->learn_frames != LEARN_FRAMES) + return; + + /* + * If the observed frequencies are too close, + * learning likely failed (only one tone seen). + * Keep the default threshold. + */ + if (st->freq_max - st->freq_min < 2) + return; + + st->freq_threshold = + (st->freq_min + st->freq_max) / 2; + if (st->debug) - print_stats(st); - if (st->freq_data < st->freq_threshold) - st->ascii |= (1 << st->ascii_bit); + printf("auto threshold: %dHz\n", + st->freq_threshold * FRAME_RATE); +} - st->ascii_bit--; - return st->ascii_bit; +/* + * Ignore silence / near silence. + * Both FIR windows will be near zero when no signal exists. + */ +static int +silent_signal(struct decoder_state *st) +{ + return (st->freq_data <= 2 && + st->freq_separator <= 2); } +/* + * Choose the lowest active tone. + * Separator frames carry tone in the separator window, + * data frames carry tone in the data window. + */ static void -print_char(struct decoder_state *st) +select_low_tone(struct decoder_state *st) { - if (st->debug) - printf("<%c,%x>", st->ascii, st->ascii); - else - putchar(st->ascii); + int f; - reset_char(st); + f = st->freq_data; + + if (f <= 0 || (st->freq_separator > 0 && + st->freq_separator < f)) + f = st->freq_separator; + + if (f <= 0) + return; + + if (f < st->freq_min) + st->freq_min = f; + + if (f > st->freq_max) + st->freq_max = f; } static void @@ -599,13 +687,6 @@ print_stats(struct decoder_state *st) } static void -reset_char(struct decoder_state *st) -{ - st->ascii = 0; - st->ascii_bit = 7; -} - -static void err(int errval, const char *msg, ...) { va_list ap; |