/* $NetBSD: load_http.c,v 1.3 2012/07/22 14:27:36 darrenr Exp $ */ /* * Copyright (C) 2012 by Darren Reed. * * See the IPFILTER.LICENCE file for details on licencing. * * Id: load_http.c,v 1.1.1.2 2012/07/22 13:44:39 darrenr */ #include "ipf.h" #include /* * Because the URL can be included twice into the buffer, once as the * full path for the "GET" and once as the "Host:", the buffer it is * put in needs to be larger than 512*2 to make room for the supporting * text. Why not just use snprintf and truncate? The warning about the * URL being too long tells you something is wrong and does not fetch * any data - just truncating the URL (with snprintf, etc) and sending * that to the server is allowing an unknown and unintentioned action * to happen. */ #define MAX_URL_LEN 512 #define LOAD_BUFSIZE (MAX_URL_LEN * 2 + 128) /* * Format expected is one addres per line, at the start of each line. */ alist_t * load_http(char *url) { int fd, len, left, port, endhdr, removed, linenum = 0; char *s, *t, *u, buffer[LOAD_BUFSIZE], *myurl; alist_t *a, *rtop, *rbot; int rem; /* * More than this would just be absurd. */ if (strlen(url) > MAX_URL_LEN) { fprintf(stderr, "load_http has a URL > %d bytes?!\n", MAX_URL_LEN); return NULL; } fd = -1; rtop = NULL; rbot = NULL; myurl = strdup(url); if (myurl == NULL) goto done; rem = sizeof(buffer); left = snprintf(buffer, rem, "GET %s HTTP/1.0\r\n", url); if (left < 0 || left > rem) goto done; rem -= left; s = myurl + 7; /* http:// */ t = strchr(s, '/'); if (t == NULL) { fprintf(stderr, "load_http has a malformed URL '%s'\n", url); goto done; } *t++ = '\0'; /* * 10 is the length of 'Host: \r\n\r\n' below. */ if (strlen(s) + strlen(buffer) + 10 > sizeof(buffer)) { fprintf(stderr, "load_http has a malformed URL '%s'\n", url); free(myurl); return NULL; } u = strchr(s, '@'); if (u != NULL) s = u + 1; /* AUTH */ left = snprintf(buffer + left, rem, "Host: %s\r\n\r\n", s); if (left < 0 || left > rem) goto done; rem -= left; u = strchr(s, ':'); if (u != NULL) { *u++ = '\0'; port = atoi(u); if (port < 0 || port > 65535) goto done; } else { port = 80; } fd = connecttcp(s, port); if (fd == -1) goto done; len = strlen(buffer); if (write(fd, buffer, len) != len) goto done; s = buffer; endhdr = 0; left = sizeof(buffer) - 1; while ((len = read(fd, s, left)) > 0) { s[len] = '\0'; left -= len; s += len; if (endhdr >= 0) { if (endhdr == 0) { t = strchr(buffer, ' '); if (t == NULL) continue; t++; if (*t != '2') break; } u = buffer; while ((t = strchr(u, '\r')) != NULL) { if (t == u) { if (*(t + 1) == '\n') { u = t + 2; endhdr = -1; break; } else t++; } else if (*(t + 1) == '\n') { endhdr++; u = t + 2; } else u = t + 1; } if (endhdr >= 0) continue; removed = (u - buffer) + 1; memmove(buffer, u, (sizeof(buffer) - left) - removed); s -= removed; left += removed; } do { t = strchr(buffer, '\n'); if (t == NULL) break; linenum++; *t = '\0'; for (u = buffer; isdigit((unsigned char)*u) || (*u == '.'); u++) continue; if (*u == '/') { char *slash; slash = u; u++; while (isdigit((unsigned char)*u)) u++; if (!isspace((unsigned char)*u) && *u) u = slash; } /* * Remove comment and continue to the next line if * the comment is at the start of the line. */ u = strchr(buffer, '#'); if (u != NULL) { *u = '\0'; if (u == buffer) continue; } /* * Trim off tailing white spaces, will include \r */ for (u = t - 1; (u >= buffer) && ISSPACE(*u); u--) *u = '\0'; a = alist_new(AF_UNSPEC, buffer); if (a != NULL) { if (rbot != NULL) rbot->al_next = a; else rtop = a; rbot = a; } else { fprintf(stderr, "%s:%d unrecognised content:%s\n", url, linenum, buffer); } t++; removed = t - buffer; memmove(buffer, t, sizeof(buffer) - left - removed); s -= removed; left += removed; } while (1); } done: if (myurl != NULL) free(myurl); if (fd != -1) close(fd); return rtop; }