proxy2ch/utils.h

#pragma once

static const char threadTimestampFmt[] = "%Y/%m/%d %H:%M:%S %Z";
static const char httpTimestampFmt[] = "%a, %d %b %Y %H:%M:%S GMT";

static void *
memmem_priv(const void *l, size_t l_len, const void *s, size_t s_len)
{
	register char *cur, *last;
	const char *cl = (const char *)l;
	const char *cs = (const char *)s;
	
	/* we need something to compare */
	if (l_len == 0 || s_len == 0)
		return NULL;
	
	/* "s" must be smaller or equal to "l" */
	if (l_len < s_len)
		return NULL;
	
	/* special case where s_len == 1 */
	if (s_len == 1)
		return (void *)memchr(l, (int)*cs, l_len);
	
	/* the last position where its possible to find "s" in "l" */
	last = (char *)cl + l_len - s_len;
	
	for (cur = (char *)cl; cur <= last; cur++)
		if (cur[0] == cs[0] && memcmp(cur, cs, s_len) == 0)
			return cur;
	
	return NULL;
}

static int decryptMail(unsigned char *decrypted, char *encrypted)
{
	char current[5]="0x";
	unsigned char *ptr = decrypted;
	current[2] = encrypted[0];
	current[3] = encrypted[1];
	unsigned int r = strtol(current,NULL,16);
	int len = strlen(encrypted);
	int n = 2;
	for(;n<len;n+=2) {
		current[2] = encrypted[n];
		current[3] = encrypted[n+1];
		unsigned int i = strtol(current,NULL,16);
		*ptr++ = i^r;
	}
	*ptr = 0;
	//fprintf(stderr,"%s->%s\n",encrypted,decrypted);
	return ptr - decrypted;
}

static size_t header_callback_proxy(char *buffer, size_t size, size_t nitems, void *userdata)
{
	BBS2chProxyConnection *conn = reinterpret_cast<BBS2chProxyConnection *>(userdata);
	if(conn->status) return size*nitems;
	
	if(!strncasecmp("Connection",buffer,10)) {
		fprintf(conn->fpw,"Connection: Close\r\n");
		return size*nitems;
	}
	else if(!strncasecmp("Transfer-Encoding",buffer,17)) {
		if(allow_chunked && strstr(buffer+19,"chunked")) {
			conn->chunked = true;
			//fprintf(stderr,"%s",buffer);
			size_t ret = fwrite(buffer,size,nitems,conn->fpw);
			return ret;
		}
		return size*nitems;
	}
	else if(conn->force5ch && !strncasecmp("Set-Cookie:",buffer,11)) {
		char *ptr = (char *)memmem_priv(buffer,size*nitems,"domain=",7);
		if(ptr) {
			char *end = ptr;
			while(*end != ';' && *end != '\r') end++;
			ptr = (char *)memmem_priv(ptr,end-ptr,"5ch.net",7);
			if(ptr) {
				fwrite(buffer,1,ptr-buffer,conn->fpw);
				fputc('2',conn->fpw);
				fwrite(ptr+1,1,size*nitems-(ptr+1-buffer),conn->fpw);
				return size*nitems;
			}
		}
		return fwrite(buffer,1,size*nitems,conn->fpw);
	}
	else {
		if (conn->bbscgi) {
			if (!strncasecmp("X-Chx-Error:", buffer, 12)) {
				const char *ptr = buffer + 12;
				while (*ptr == ' ') ptr++;
				log_printf(0, "Posting to bbs.cgi has been cancelled. Reason: %s", ptr);
				if (*ptr == 'E') {
					int code = atoi(ptr+1);
					if ((code >= 3310 && code <= 3311) || /* inconsistent with User-Agent or something? */
						(code >= 3320 && code <= 3324) || /* key expiration? */
						(code >= 3390 && code <= 3392))   /* 3390: BAN, 3391-3392: key expiration? */
						conn->setMonaKey("", code);
				}
			}
			else if (!strncasecmp("X-MonaKey:", buffer, 10)) {
				const char *ptr = buffer + 10;
				while (*ptr == ' ') ptr++;
				const char *end = ptr;
				while (*end != '\n' && *end != '\r' && *end) end++;
				conn->setMonaKey(std::string(ptr, end-ptr), 0);
			}
		}
		size_t ret = fwrite(buffer,size,nitems,conn->fpw);
		//fprintf(stderr,"%s",buffer);
		if(!memcmp(buffer,"\r\n",2)) {
			fflush(conn->fpw);
			conn->status = 1;
		}
		return ret;
	}
}

static size_t header_callback_bbscgi(char *buffer, size_t size, size_t nitems, void *userdata)
{
	BBS2chProxyConnection *conn = reinterpret_cast<BBS2chProxyConnection *>(userdata);
	if(conn->status) return size*nitems;
	
	if(!strncasecmp("Connection",buffer,10)) {
		conn->responseHeaders.append("Connection: Close\r\n");
		return size*nitems;
	}
	else if(!strncasecmp("Transfer-Encoding",buffer,17)) {
		if(allow_chunked && strstr(buffer+19,"chunked")) {
			conn->chunked = true;
			//fprintf(stderr,"%s",buffer);
			conn->responseHeaders.append(buffer, size*nitems);
		}
		return size*nitems;
	}
	else if(conn->force5ch && !strncasecmp("Set-Cookie:",buffer,11)) {
		char *ptr = (char *)memmem_priv(buffer,size*nitems,"domain=",7);
		if(ptr) {
			char *end = ptr;
			while(*end != ';' && *end != '\r') end++;
			ptr = (char *)memmem_priv(ptr,end-ptr,"5ch.net",7);
			if(ptr) {
				conn->responseHeaders.append(buffer, ptr-buffer);
				conn->responseHeaders.append(1, '2');
				conn->responseHeaders.append(ptr+1, size*nitems-(ptr+1-buffer));
				return size*nitems;
			}
		}
		conn->responseHeaders.append(buffer, size*nitems);
		return size*nitems;
	}
	else {
		if (!strncasecmp("X-Chx-Error:", buffer, 12)) {
			const char *ptr = buffer + 12;
			while (*ptr == ' ') ptr++;
			log_printf(0, "Posting to bbs.cgi has been cancelled. Reason: %s", ptr);
			if (*ptr == 'E') {
				int code = atoi(ptr+1);
				if ((code >= 3310 && code <= 3311) || /* inconsistent with User-Agent or something? */
					(code >= 3320 && code <= 3324) || /* key expiration? */
					(code >= 3390 && code <= 3392))   /* 3390: BAN, 3391-3392: key expiration? */
				{
					conn->setMonaKey("", code);
					conn->status = 2;
					return 0;
				}
			}
		}
		else if (!strncasecmp("X-MonaKey:", buffer, 10)) {
			const char *ptr = buffer + 10;
			while (*ptr == ' ') ptr++;
			const char *end = ptr;
			while (*end != '\n' && *end != '\r' && *end) end++;
			conn->setMonaKey(std::string(ptr, end-ptr), 0);
		}
		conn->responseHeaders.append(buffer, size*nitems);
		//fprintf(stderr,"%s",buffer);
		if(!memcmp(buffer,"\r\n",2)) {
			fwrite(conn->responseHeaders.data(), 1, conn->responseHeaders.size(), conn->fpw);
			fflush(conn->fpw);
			conn->status = 1;
		}
		return size*nitems;
	}
}

static size_t write_callback_proxy(char *buffer, size_t size, size_t nitems, void *userdata)
{
	BBS2chProxyConnection *conn = reinterpret_cast<BBS2chProxyConnection *>(userdata);
	if(conn->chunked) fprintf(conn->fpw,"%lx\r\n",size*nitems);
	size_t ret = fwrite(buffer,size,nitems,conn->fpw);
	if(conn->chunked) fprintf(conn->fpw,"\r\n");
	fflush(conn->fpw);
	return ret;
}

static size_t header_callback_download(char *buffer, size_t size, size_t nitems, void *userdata)
{
	DataStorage *data = reinterpret_cast<DataStorage *>(userdata);
	if(!strncasecmp("Connection",buffer,10)) {
		data->appendBytes("Connection: Close\r\n",19);
		return size*nitems;
	}
	else if(!strncasecmp("Transfer-Encoding",buffer,17)) {
		return size*nitems;
	}
	else {
		data->appendBytes(buffer,size*nitems);
		return size*nitems;
	}
}

static size_t write_callback_download(char *buffer, size_t size, size_t nitems, void *userdata)
{
	DataStorage *data = reinterpret_cast<DataStorage *>(userdata);
	size_t downloaded = size*nitems;
	data->appendBytes(buffer, downloaded);
	return downloaded;
}

static size_t read_callback_proxy(char *buffer, size_t size, size_t nitems, void *userdata)
{
	BBS2chProxyConnection *conn = reinterpret_cast<BBS2chProxyConnection *>(userdata);
	if(size*nitems < 1) return 0;
	if(conn->content_length) {
		size_t bytesToRead = conn->content_length;
		if(size*nitems < conn->content_length) bytesToRead = size*nitems;
		size_t ret = fread(buffer,1,bytesToRead,conn->fpr);
		conn->content_length -= ret;
		return ret;
	}
	return 0;
}

static void sendBasicHeaders(int respCode, const char *respMsg, FILE *fpw)
{
	char date[256];
	time_t now = time(0);
	strftime(date, 256, httpTimestampFmt, gmtime(&now));
	if(0 > fprintf(fpw, "HTTP/1.1 %d %s\r\n",respCode,respMsg)) return;
	if(0 > fprintf(fpw, "Connection: Close\r\n")) return;
	if(0 > fprintf(fpw, "Server: 2ch Proxy\r\n")) return;
	if(0 > fprintf(fpw, "Date: %s\r\n",date)) return;
	fflush(fpw);
}

static void sendResponse(int respCode, const char *respMsg, FILE *fpw)
{
	sendBasicHeaders(respCode, respMsg, fpw);
	if(0 > fprintf(fpw, "Content-Type: text/plain; charset=UTF-8\r\n")) return;
	if(0 > fprintf(fpw, "\r\n")) return;
	if(respCode >= 400) {
		if(0 > fprintf(fpw, "　　  ∧＿∧　　 ／￣￣￣￣￣\n")) return;
		if(0 > fprintf(fpw, "　　（ ´∀｀）＜　%s\n",respMsg)) return;
		if(0 > fprintf(fpw, "　　（　　 　）  ＼＿＿＿＿＿\n")) return;
		if(0 > fprintf(fpw, "　　 │ │  │\n")) return;
		if(0 > fprintf(fpw, "　　（＿_）＿）\n")) return;
	}
	fflush(fpw);
}

static double getCurrentTime(void)
{
#ifdef _WIN32
	SYSTEMTIME st;
	FILETIME ft;
	GetLocalTime(&st);
	SystemTimeToFileTime(&st, &ft);
	unsigned long long now = ft.dwHighDateTime;
	now <<= 32;
	now |= ft.dwLowDateTime;
	return (double)(now * 1e-7 - 11644473600.0);
#else
	struct timeval tv;
	gettimeofday(&tv, NULL);
	return (double)(tv.tv_sec + tv.tv_usec * 1e-6);
#endif
}

static std::string decodeURIComponent(const char *input, size_t inputLength, bool decodePlus)
{
	std::string output;
	for (int i=0;i<inputLength;i++) {
		if (input[i] == '%') {
			if (i < inputLength - 2) {
				char from[3];
				char *end;
				from[0] = input[i+1];
				from[1] = input[i+2];
				from[2] = 0;
				unsigned long n = strtoul(from, &end, 16);
				if (n < 256 && end == from+2) {
					output.append(1, n);
					i += 2;
					continue;
				}
			}
		}
		else if (decodePlus && input[i] == '+') {
			output.append(" ");
			continue;
		}
		output.append(1, input[i]);
	}
	return output;
}

static std::string encodeURIComponent(const char *input, size_t inputLength, bool spaceAsPlus)
{
	std::string output;
	for (int i=0;i<inputLength;i++) {
		unsigned char c = (unsigned char)input[i];
		if ((c >= '0' && c <= '9') ||
			(c >= 'A' && c <= 'Z') ||
			(c >= 'a' && c <= 'z') ||
			(c == '*') || (c == '-') || (c == '.') || (c == '_')) {
			output.append(1, c);
		}
		else if (c == ' ' && spaceAsPlus) {
			output.append("+");
		}
		else {
			char percentEncoded[4];
			snprintf(percentEncoded, 4, "%%%02X", c);
			output.append(percentEncoded);
		}
	}
	return output;
}

static void appendPostSignature(const char *body, const std::string &userAgent, const std::string &monaKey, curl_slist *headers)
{
	std::map<std::string, std::string> fields;
	const char *ptr = body;
	while (1) {
		const char *tmp = ptr;
		while (*tmp != '=' && *tmp != 0) tmp++;
		if (*tmp == 0) break;
		std::string key(ptr, tmp-ptr);
		tmp++;
		ptr = tmp;
		while (*tmp != '&' && *tmp != 0) tmp++;
		fields.insert(std::make_pair(key, decodeURIComponent(ptr, tmp-ptr, true)));
		if (*tmp == 0) break;
		ptr = tmp + 1;
	}
	char nonce[32];
	snprintf(nonce, 32, "%.3f", getCurrentTime());
	std::string message;
	message.append(fields["bbs"]);
	message.append("<>");
	message.append(fields["key"]);
	message.append("<>");
	message.append(fields["time"]);
	message.append("<>");
	message.append(fields["FROM"]);
	message.append("<>");
	message.append(fields["mail"]);
	message.append("<>");
	message.append(fields["MESSAGE"]);
	message.append("<>");
	message.append(fields["subject"]);
	message.append("<>");
	message.append(userAgent);
	message.append("<>");
	message.append(monaKey);
	message.append("<>");
	message.append("<>");
	message.append(nonce);
	unsigned char digest[32];
	char digestStr[65];
	static const char *table = "0123456789abcdef";
	proxy2ch_HMAC_SHA256(hmacKey, strlen(hmacKey), message.data(), message.length(), digest);
	for (int i=0; i<32; i++) {
		unsigned char c = digest[i];
		unsigned char upper = (c >> 4) & 0xf;
		unsigned char lower = c & 0xf;
		digestStr[i*2] = table[upper];
		digestStr[i*2+1] = table[lower];
	}
	digestStr[64] = 0;
	char header[256];
	snprintf(header, 256, "X-APIKey: %s", appKey);
	headers = curl_slist_append(headers, header);
	log_printf(1, "Appended header \"%s\"\n", header);
	snprintf(header, 256, "X-PostSig: %s", digestStr);
	headers = curl_slist_append(headers, header);
	log_printf(1, "Appended header \"%s\"\n", header);
	snprintf(header, 256, "X-PostNonce: %s", nonce);
	headers = curl_slist_append(headers, header);
	log_printf(1, "Appended header \"%s\"\n", header);
	snprintf(header, 256, "X-MonaKey: %s", monaKey.c_str());
	headers = curl_slist_append(headers, header);
	log_printf(1, "Appended header \"%s\"\n", header);
}

#ifdef _WIN32
const char * strp_weekdays[] = 
    { "sunday", "monday", "tuesday", "wednesday", "thursday", "friday", "saturday"};
const char * strp_monthnames[] = 
    { "january", "february", "march", "april", "may", "june", "july", "august", "september", "october", "november", "december"};
bool strp_atoi(const char * & s, int & result, int low, int high, int offset)
    {
    bool worked = false;
    char * end;
    unsigned long num = strtoul(s, & end, 10);
    if (num >= (unsigned long)low && num <= (unsigned long)high)
        {
        result = (int)(num + offset);
        s = end;
        worked = true;
        }
    return worked;
    }
char * strptime(const char *s, const char *format, struct tm *tm)
    {
    bool working = true;
    while (working && *format && *s)
        {
        switch (*format)
            {
        case '%':
            {
            ++format;
            switch (*format)
                {
            case 'a':
            case 'A': // weekday name
                tm->tm_wday = -1;
                working = false;
                for (size_t i = 0; i < 7; ++ i)
                    {
                    size_t len = strlen(strp_weekdays[i]);
                    if (!strnicmp(strp_weekdays[i], s, len))
                        {
                        tm->tm_wday = i;
                        s += len;
                        working = true;
                        break;
                        }
                    else if (!strnicmp(strp_weekdays[i], s, 3))
                        {
                        tm->tm_wday = i;
                        s += 3;
                        working = true;
                        break;
                        }
                    }
                break;
            case 'b':
            case 'B':
            case 'h': // month name
                tm->tm_mon = -1;
                working = false;
                for (size_t i = 0; i < 12; ++ i)
                    {
                    size_t len = strlen(strp_monthnames[i]);
                    if (!strnicmp(strp_monthnames[i], s, len))
                        {
                        tm->tm_mon = i;
                        s += len;
                        working = true;
                        break;
                        }
                    else if (!strnicmp(strp_monthnames[i], s, 3))
                        {
                        tm->tm_mon = i;
                        s += 3;
                        working = true;
                        break;
                        }
                    }
                break;
            case 'd':
            case 'e': // day of month number
                working = strp_atoi(s, tm->tm_mday, 1, 31, 0);
                break;
            case 'D': // %m/%d/%y
                {
                const char * s_save = s;
                working = strp_atoi(s, tm->tm_mon, 1, 12, -1);
                if (working && *s == '/')
                    {
                    ++ s;
                    working = strp_atoi(s, tm->tm_mday, 1, 31, 0);
                    if (working && *s == '/')
                        {
                        ++ s;
                        working = strp_atoi(s, tm->tm_year, 0, 99, 0);
                        if (working && tm->tm_year < 69)
                            tm->tm_year += 100;
                        }
                    }
                if (!working)
                    s = s_save;
                }
                break;
            case 'H': // hour
                working = strp_atoi(s, tm->tm_hour, 0, 23, 0);
                break;
            case 'I': // hour 12-hour clock
                working = strp_atoi(s, tm->tm_hour, 1, 12, 0);
                break;
            case 'j': // day number of year
                working = strp_atoi(s, tm->tm_yday, 1, 366, -1);
                break;
            case 'm': // month number
                working = strp_atoi(s, tm->tm_mon, 1, 12, -1);
                break;
            case 'M': // minute
                working = strp_atoi(s, tm->tm_min, 0, 59, 0);
                break;
            case 'n': // arbitrary whitespace
            case 't':
                while (isspace((int)*s)) 
                    ++s;
                break;
            case 'p': // am / pm
                if (!strnicmp(s, "am", 2))
                    { // the hour will be 1 -> 12 maps to 12 am, 1 am .. 11 am, 12 noon 12 pm .. 11 pm
                    if (tm->tm_hour == 12) // 12 am == 00 hours
                        tm->tm_hour = 0;
                    }
                else if (!strnicmp(s, "pm", 2))
                    {
                    if (tm->tm_hour < 12) // 12 pm == 12 hours
                        tm->tm_hour += 12; // 1 pm -> 13 hours, 11 pm -> 23 hours
                    }
                else
                    working = false;
                break;
            case 'r': // 12 hour clock %I:%M:%S %p
                {
                const char * s_save = s;
                working = strp_atoi(s, tm->tm_hour, 1, 12, 0);
                if (working && *s == ':')
                    {
                    ++ s;
                    working = strp_atoi(s, tm->tm_min, 0, 59, 0);
                    if (working && *s == ':')
                        {
                        ++ s;
                        working = strp_atoi(s, tm->tm_sec, 0, 60, 0);
                        if (working && isspace((int)*s))
                            {
                            ++ s;
                            while (isspace((int)*s)) 
                                ++s;
                            if (!strnicmp(s, "am", 2))
                                { // the hour will be 1 -> 12 maps to 12 am, 1 am .. 11 am, 12 noon 12 pm .. 11 pm
                                if (tm->tm_hour == 12) // 12 am == 00 hours
                                    tm->tm_hour = 0;
                                }
                            else if (!strnicmp(s, "pm", 2))
                                {
                                if (tm->tm_hour < 12) // 12 pm == 12 hours
                                    tm->tm_hour += 12; // 1 pm -> 13 hours, 11 pm -> 23 hours
                                }
                            else
                                working = false;
                            }
                        }
                    }
                if (!working)
                    s = s_save;
                }
                break;
            case 'R': // %H:%M
                {
                const char * s_save = s;
                working = strp_atoi(s, tm->tm_hour, 0, 23, 0);
                if (working && *s == ':')
                    {
                    ++ s;
                    working = strp_atoi(s, tm->tm_min, 0, 59, 0);
                    }
                if (!working)
                    s = s_save;
                }
                break;
            case 'S': // seconds
                working = strp_atoi(s, tm->tm_sec, 0, 60, 0);
                break;
            case 'T': // %H:%M:%S
                {
                const char * s_save = s;
                working = strp_atoi(s, tm->tm_hour, 0, 23, 0);
                if (working && *s == ':')
                    {
                    ++ s;
                    working = strp_atoi(s, tm->tm_min, 0, 59, 0);
                    if (working && *s == ':')
                        {
                        ++ s;
                        working = strp_atoi(s, tm->tm_sec, 0, 60, 0);
                        }
                    }
                if (!working)
                    s = s_save;
                }
                break;
            case 'w': // weekday number 0->6 sunday->saturday
                working = strp_atoi(s, tm->tm_wday, 0, 6, 0);
                break;
            case 'Y': // year
                working = strp_atoi(s, tm->tm_year, 1900, 65535, -1900);
                break;
            case 'y': // 2-digit year
                working = strp_atoi(s, tm->tm_year, 0, 99, 0);
                if (working && tm->tm_year < 69)
                    tm->tm_year += 100;
                break;
            case '%': // escaped
                if (*s != '%')
                    working = false;
                ++s;
                break;
            default:
                working = false;
                }
            }
            break;
        case ' ':
        case '\t':
        case '\r':
        case '\n':
        case '\f':
        case '\v':
            // zero or more whitespaces:
            while (isspace((int)*s))
                ++ s;
            break;
        default:
            // match character
            if (*s != *format)
                working = false;
            else
                ++s;
            break;
            }
        ++format;
        }
    return (working?(char *)s:0);
}
#endif