FreeCalypso > hg > freecalypso-tools
view rvinterf/old/format_g23.c @ 180:e50c3aa1152a
doc/Melody_E1 written
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Mon, 27 Mar 2017 21:38:45 +0000 |
parents | e7502631a0f9 |
children |
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/* * This module implements the decoding of G23 trace packets into * human-readable form - or more precisely, traces, system primitives * and other packets that can be emitted through GPF on targets. * The decoding is based on my (Space Falcon's) understanding * of the packet format, which is in turn based on the GPF sources * available to us, now integrated under gsm-fw/gpf. */ #include <sys/types.h> #include <ctype.h> #include <stdio.h> #include <string.h> #include <strings.h> #include "../include/pktmux.h" #include "../include/limits.h" extern u_char rxpkt[]; extern size_t rxpkt_len; extern char fmtbuf[]; static char *fmtbuf_ptr; static int basic_checks() { int i, c; if (rxpkt_len < 17) return(0); /* check version bits in the header byte */ if ((rxpkt[1] & 0xC0) != 0x80) return(0); /* check the length */ c = rxpkt[2] | rxpkt[3] << 8; if (c + 4 != rxpkt_len) return(0); /* ensure that the "from" and "to" are printable ASCII */ for (i = 8; i < 16; i++) { c = rxpkt[i]; if (c < ' ' || c > '~') return(0); } /* basic checks pass */ return(1); } static int psprim_extra_checks() { int i, c; if (rxpkt_len < 24) return(0); /* "original rcvr" field needs to be printable ASCII */ for (i = 16; i < 20; i++) { c = rxpkt[i]; if (c < ' ' || c > '~') return(0); } /* checks pass */ return(1); } static void print_malformed() { int i; char *dp; dp = fmtbuf; strcpy(dp, "G23 UNK:"); dp += 8; for (i = 1; i < rxpkt_len; i++) { sprintf(dp, " %02X", rxpkt[i]); dp += 3; } *dp = '\0'; output_line(fmtbuf); } static int entity_name_well_formed(p) char *p; { int i, len; if (!isupper(p[0])) return(0); for (i = 0; i < 4; i++) if (!isalnum(p[i])) break; len = i; for (; i < 4; i++) if (p[i] != ' ') return(0); return(len); } static void print_entity_name(raw) char *raw; { int len; len = entity_name_well_formed(raw); if (len) sprintf(fmtbuf_ptr, "%.*s", len, raw); else sprintf(fmtbuf_ptr, "\"%.4s\"", raw); fmtbuf_ptr = index(fmtbuf_ptr, '\0'); } static void print_common_hdr(typestr) char *typestr; { sprintf(fmtbuf, "G23 %s id=%02X ts=%02X%02X%02X%02X ", typestr, rxpkt[1], rxpkt[7], rxpkt[6], rxpkt[5], rxpkt[4]); fmtbuf_ptr = index(fmtbuf, '\0'); print_entity_name(rxpkt + 8); *fmtbuf_ptr++ = '-'; *fmtbuf_ptr++ = '>'; print_entity_name(rxpkt + 12); *fmtbuf_ptr++ = ' '; } static void format_text(start_off) { int i, c; *fmtbuf_ptr++ = '\"'; for (i = start_off; i < rxpkt_len; i++) { c = rxpkt[i]; if (c & 0x80) { *fmtbuf_ptr++ = 'M'; *fmtbuf_ptr++ = '-'; c &= 0x7F; } if (c < 0x20) { *fmtbuf_ptr++ = '^'; *fmtbuf_ptr++ = c + '@'; } else if (c == 0x7F) { *fmtbuf_ptr++ = '^'; *fmtbuf_ptr++ = '?'; } else *fmtbuf_ptr++ = c; } *fmtbuf_ptr++ = '\"'; *fmtbuf_ptr = '\0'; output_line(fmtbuf); } static void format_compressed_trace(start_off) { int i; i = start_off + 1; sprintf(fmtbuf_ptr, "%d", rxpkt[i+1] << 8 | rxpkt[i]); fmtbuf_ptr = index(fmtbuf_ptr, '\0'); i += 4; for (; i < rxpkt_len; i++) { sprintf(fmtbuf_ptr, " %02X", rxpkt[i]); fmtbuf_ptr += 3; } *fmtbuf_ptr = '\0'; output_line(fmtbuf); } static void format_trace() { int i; i = 16; if (rxpkt[i] < 0x20) { sprintf(fmtbuf_ptr, "tc=%02X ", rxpkt[i]); fmtbuf_ptr += 6; i++; } if (rxpkt_len - i >= 5 && rxpkt[i] == '%' && !rxpkt[i+3] && !rxpkt[i+4]) format_compressed_trace(i); else format_text(i); } static void format_psprim() { int i; /* original destination */ *fmtbuf_ptr++ = '('; print_entity_name(rxpkt + 16); *fmtbuf_ptr++ = ')'; /* opcode */ sprintf(fmtbuf_ptr, " %02X%02X%02X%02X", rxpkt[23], rxpkt[22], rxpkt[21], rxpkt[20]); fmtbuf_ptr += 9; for (i = 24; i < rxpkt_len; i++) { sprintf(fmtbuf_ptr, " %02X", rxpkt[i]); fmtbuf_ptr += 3; } *fmtbuf_ptr = '\0'; output_line(fmtbuf); } void print_g23_trace() { if (!basic_checks()) { print_malformed(); return; } /* dispatch by type */ switch (rxpkt[1] & 0x30) { case 0x10: /* PS primitive */ if (psprim_extra_checks()) { print_common_hdr("PSprim"); format_psprim(); } else print_malformed(); return; case 0x20: /* trace */ print_common_hdr("trace"); format_trace(); return; case 0x30: /* system primitive */ print_common_hdr("sysprim"); format_text(16); return; default: print_malformed(); } }