Mercurial > hg > nginx
view src/core/ngx_parse_time.c @ 7883:41f4bd4c51f1
Disabled control characters and space in header names.
Control characters (0x00-0x1f, 0x7f), space, and colon were never allowed in
header names. The only somewhat valid use is header continuation which nginx
never supported and which is explicitly obsolete by RFC 7230.
Previously, such headers were considered invalid and were ignored by default
(as per ignore_invalid_headers directive). With this change, such headers
are unconditionally rejected.
It is expected to make nginx more resilient to various attacks, in particular,
with ignore_invalid_headers switched off (which is inherently unsecure, though
nevertheless sometimes used in the wild).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 28 Jun 2021 18:01:18 +0300 |
parents | b38a8f0ca4a2 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> static ngx_uint_t mday[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; time_t ngx_parse_http_time(u_char *value, size_t len) { u_char *p, *end; ngx_int_t month; ngx_uint_t day, year, hour, min, sec; uint64_t time; enum { no = 0, rfc822, /* Tue, 10 Nov 2002 23:50:13 */ rfc850, /* Tuesday, 10-Dec-02 23:50:13 */ isoc /* Tue Dec 10 23:50:13 2002 */ } fmt; fmt = 0; end = value + len; #if (NGX_SUPPRESS_WARN) day = 32; year = 2038; #endif for (p = value; p < end; p++) { if (*p == ',') { break; } if (*p == ' ') { fmt = isoc; break; } } for (p++; p < end; p++) { if (*p != ' ') { break; } } if (end - p < 18) { return NGX_ERROR; } if (fmt != isoc) { if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9') { return NGX_ERROR; } day = (*p - '0') * 10 + (*(p + 1) - '0'); p += 2; if (*p == ' ') { if (end - p < 18) { return NGX_ERROR; } fmt = rfc822; } else if (*p == '-') { fmt = rfc850; } else { return NGX_ERROR; } p++; } switch (*p) { case 'J': month = *(p + 1) == 'a' ? 0 : *(p + 2) == 'n' ? 5 : 6; break; case 'F': month = 1; break; case 'M': month = *(p + 2) == 'r' ? 2 : 4; break; case 'A': month = *(p + 1) == 'p' ? 3 : 7; break; case 'S': month = 8; break; case 'O': month = 9; break; case 'N': month = 10; break; case 'D': month = 11; break; default: return NGX_ERROR; } p += 3; if ((fmt == rfc822 && *p != ' ') || (fmt == rfc850 && *p != '-')) { return NGX_ERROR; } p++; if (fmt == rfc822) { if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9' || *(p + 2) < '0' || *(p + 2) > '9' || *(p + 3) < '0' || *(p + 3) > '9') { return NGX_ERROR; } year = (*p - '0') * 1000 + (*(p + 1) - '0') * 100 + (*(p + 2) - '0') * 10 + (*(p + 3) - '0'); p += 4; } else if (fmt == rfc850) { if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9') { return NGX_ERROR; } year = (*p - '0') * 10 + (*(p + 1) - '0'); year += (year < 70) ? 2000 : 1900; p += 2; } if (fmt == isoc) { if (*p == ' ') { p++; } if (*p < '0' || *p > '9') { return NGX_ERROR; } day = *p++ - '0'; if (*p != ' ') { if (*p < '0' || *p > '9') { return NGX_ERROR; } day = day * 10 + (*p++ - '0'); } if (end - p < 14) { return NGX_ERROR; } } if (*p++ != ' ') { return NGX_ERROR; } if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9') { return NGX_ERROR; } hour = (*p - '0') * 10 + (*(p + 1) - '0'); p += 2; if (*p++ != ':') { return NGX_ERROR; } if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9') { return NGX_ERROR; } min = (*p - '0') * 10 + (*(p + 1) - '0'); p += 2; if (*p++ != ':') { return NGX_ERROR; } if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9') { return NGX_ERROR; } sec = (*p - '0') * 10 + (*(p + 1) - '0'); if (fmt == isoc) { p += 2; if (*p++ != ' ') { return NGX_ERROR; } if (*p < '0' || *p > '9' || *(p + 1) < '0' || *(p + 1) > '9' || *(p + 2) < '0' || *(p + 2) > '9' || *(p + 3) < '0' || *(p + 3) > '9') { return NGX_ERROR; } year = (*p - '0') * 1000 + (*(p + 1) - '0') * 100 + (*(p + 2) - '0') * 10 + (*(p + 3) - '0'); } if (hour > 23 || min > 59 || sec > 59) { return NGX_ERROR; } if (day == 29 && month == 1) { if ((year & 3) || ((year % 100 == 0) && (year % 400) != 0)) { return NGX_ERROR; } } else if (day > mday[month]) { return NGX_ERROR; } /* * shift new year to March 1 and start months from 1 (not 0), * it is needed for Gauss' formula */ if (--month <= 0) { month += 12; year -= 1; } /* Gauss' formula for Gregorian days since March 1, 1 BC */ time = (uint64_t) ( /* days in years including leap years since March 1, 1 BC */ 365 * year + year / 4 - year / 100 + year / 400 /* days before the month */ + 367 * month / 12 - 30 /* days before the day */ + day - 1 /* * 719527 days were between March 1, 1 BC and March 1, 1970, * 31 and 28 days were in January and February 1970 */ - 719527 + 31 + 28) * 86400 + hour * 3600 + min * 60 + sec; #if (NGX_TIME_T_SIZE <= 4) if (time > 0x7fffffff) { return NGX_ERROR; } #endif return (time_t) time; }