Mercurial > hg > nginx
view src/core/ngx_proxy_protocol.c @ 8045:aa28c802409f
Resolver: make TCP write timer event cancelable.
Similar to 70e65bf8dfd7, the change is made to ensure that the ability to
cancel resolver tasks is fully controlled by the caller. As mentioned in the
referenced commit, it is safe to make this timer cancelable because resolve
tasks can have their own timeouts that are not cancelable.
The scenario where this may become a problem is a periodic background resolve
task (not tied to a specific request or a client connection), which receives a
response with short TTL, large enough to warrant fallback to a TCP query.
With each event loop wakeup, we either have a previously set write timer
instance or schedule a new one. The non-cancelable write timer can delay or
block graceful shutdown of a worker even if the ngx_resolver_ctx_t->cancelable
flag is set by the API user, and there are no other tasks or connections.
We use the resolver API in this way to maintain the list of upstream server
addresses specified with the 'resolve' parameter, and there could be third-party
modules implementing similar logic.
author | Aleksei Bavshin <a.bavshin@f5.com> |
---|---|
date | Wed, 01 Jun 2022 20:17:23 -0700 |
parents | 89adf49fe76a |
children | 017fd847f4f7 |
line wrap: on
line source
/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #define NGX_PROXY_PROTOCOL_AF_INET 1 #define NGX_PROXY_PROTOCOL_AF_INET6 2 #define ngx_proxy_protocol_parse_uint16(p) ((p)[0] << 8 | (p)[1]) typedef struct { u_char signature[12]; u_char version_command; u_char family_transport; u_char len[2]; } ngx_proxy_protocol_header_t; typedef struct { u_char src_addr[4]; u_char dst_addr[4]; u_char src_port[2]; u_char dst_port[2]; } ngx_proxy_protocol_inet_addrs_t; typedef struct { u_char src_addr[16]; u_char dst_addr[16]; u_char src_port[2]; u_char dst_port[2]; } ngx_proxy_protocol_inet6_addrs_t; static u_char *ngx_proxy_protocol_read_addr(ngx_connection_t *c, u_char *p, u_char *last, ngx_str_t *addr); static u_char *ngx_proxy_protocol_read_port(u_char *p, u_char *last, in_port_t *port, u_char sep); static u_char *ngx_proxy_protocol_v2_read(ngx_connection_t *c, u_char *buf, u_char *last); u_char * ngx_proxy_protocol_read(ngx_connection_t *c, u_char *buf, u_char *last) { size_t len; u_char *p; ngx_proxy_protocol_t *pp; static const u_char signature[] = "\r\n\r\n\0\r\nQUIT\n"; p = buf; len = last - buf; if (len >= sizeof(ngx_proxy_protocol_header_t) && memcmp(p, signature, sizeof(signature) - 1) == 0) { return ngx_proxy_protocol_v2_read(c, buf, last); } if (len < 8 || ngx_strncmp(p, "PROXY ", 6) != 0) { goto invalid; } p += 6; len -= 6; if (len >= 7 && ngx_strncmp(p, "UNKNOWN", 7) == 0) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol unknown protocol"); p += 7; goto skip; } if (len < 5 || ngx_strncmp(p, "TCP", 3) != 0 || (p[3] != '4' && p[3] != '6') || p[4] != ' ') { goto invalid; } p += 5; pp = ngx_pcalloc(c->pool, sizeof(ngx_proxy_protocol_t)); if (pp == NULL) { return NULL; } p = ngx_proxy_protocol_read_addr(c, p, last, &pp->src_addr); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_addr(c, p, last, &pp->dst_addr); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_port(p, last, &pp->src_port, ' '); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_port(p, last, &pp->dst_port, CR); if (p == NULL) { goto invalid; } if (p == last) { goto invalid; } if (*p++ != LF) { goto invalid; } ngx_log_debug4(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol src: %V %d, dst: %V %d", &pp->src_addr, pp->src_port, &pp->dst_addr, pp->dst_port); c->proxy_protocol = pp; return p; skip: for ( /* void */ ; p < last - 1; p++) { if (p[0] == CR && p[1] == LF) { return p + 2; } } invalid: ngx_log_error(NGX_LOG_ERR, c->log, 0, "broken header: \"%*s\"", (size_t) (last - buf), buf); return NULL; } static u_char * ngx_proxy_protocol_read_addr(ngx_connection_t *c, u_char *p, u_char *last, ngx_str_t *addr) { size_t len; u_char ch, *pos; pos = p; for ( ;; ) { if (p == last) { return NULL; } ch = *p++; if (ch == ' ') { break; } if (ch != ':' && ch != '.' && (ch < 'a' || ch > 'f') && (ch < 'A' || ch > 'F') && (ch < '0' || ch > '9')) { return NULL; } } len = p - pos - 1; addr->data = ngx_pnalloc(c->pool, len); if (addr->data == NULL) { return NULL; } ngx_memcpy(addr->data, pos, len); addr->len = len; return p; } static u_char * ngx_proxy_protocol_read_port(u_char *p, u_char *last, in_port_t *port, u_char sep) { size_t len; u_char *pos; ngx_int_t n; pos = p; for ( ;; ) { if (p == last) { return NULL; } if (*p++ == sep) { break; } } len = p - pos - 1; n = ngx_atoi(pos, len); if (n < 0 || n > 65535) { return NULL; } *port = (in_port_t) n; return p; } u_char * ngx_proxy_protocol_write(ngx_connection_t *c, u_char *buf, u_char *last) { ngx_uint_t port, lport; if (last - buf < NGX_PROXY_PROTOCOL_MAX_HEADER) { return NULL; } if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK) { return NULL; } switch (c->sockaddr->sa_family) { case AF_INET: buf = ngx_cpymem(buf, "PROXY TCP4 ", sizeof("PROXY TCP4 ") - 1); break; #if (NGX_HAVE_INET6) case AF_INET6: buf = ngx_cpymem(buf, "PROXY TCP6 ", sizeof("PROXY TCP6 ") - 1); break; #endif default: return ngx_cpymem(buf, "PROXY UNKNOWN" CRLF, sizeof("PROXY UNKNOWN" CRLF) - 1); } buf += ngx_sock_ntop(c->sockaddr, c->socklen, buf, last - buf, 0); *buf++ = ' '; buf += ngx_sock_ntop(c->local_sockaddr, c->local_socklen, buf, last - buf, 0); port = ngx_inet_get_port(c->sockaddr); lport = ngx_inet_get_port(c->local_sockaddr); return ngx_slprintf(buf, last, " %ui %ui" CRLF, port, lport); } static u_char * ngx_proxy_protocol_v2_read(ngx_connection_t *c, u_char *buf, u_char *last) { u_char *end; size_t len; socklen_t socklen; ngx_uint_t version, command, family, transport; ngx_sockaddr_t src_sockaddr, dst_sockaddr; ngx_proxy_protocol_t *pp; ngx_proxy_protocol_header_t *header; ngx_proxy_protocol_inet_addrs_t *in; #if (NGX_HAVE_INET6) ngx_proxy_protocol_inet6_addrs_t *in6; #endif header = (ngx_proxy_protocol_header_t *) buf; buf += sizeof(ngx_proxy_protocol_header_t); version = header->version_command >> 4; if (version != 2) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "unknown PROXY protocol version: %ui", version); return NULL; } len = ngx_proxy_protocol_parse_uint16(header->len); if ((size_t) (last - buf) < len) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "header is too large"); return NULL; } end = buf + len; command = header->version_command & 0x0f; /* only PROXY is supported */ if (command != 1) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported command %ui", command); return end; } transport = header->family_transport & 0x0f; /* only STREAM is supported */ if (transport != 1) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported transport %ui", transport); return end; } pp = ngx_pcalloc(c->pool, sizeof(ngx_proxy_protocol_t)); if (pp == NULL) { return NULL; } family = header->family_transport >> 4; switch (family) { case NGX_PROXY_PROTOCOL_AF_INET: if ((size_t) (end - buf) < sizeof(ngx_proxy_protocol_inet_addrs_t)) { return NULL; } in = (ngx_proxy_protocol_inet_addrs_t *) buf; src_sockaddr.sockaddr_in.sin_family = AF_INET; src_sockaddr.sockaddr_in.sin_port = 0; memcpy(&src_sockaddr.sockaddr_in.sin_addr, in->src_addr, 4); dst_sockaddr.sockaddr_in.sin_family = AF_INET; dst_sockaddr.sockaddr_in.sin_port = 0; memcpy(&dst_sockaddr.sockaddr_in.sin_addr, in->dst_addr, 4); pp->src_port = ngx_proxy_protocol_parse_uint16(in->src_port); pp->dst_port = ngx_proxy_protocol_parse_uint16(in->dst_port); socklen = sizeof(struct sockaddr_in); buf += sizeof(ngx_proxy_protocol_inet_addrs_t); break; #if (NGX_HAVE_INET6) case NGX_PROXY_PROTOCOL_AF_INET6: if ((size_t) (end - buf) < sizeof(ngx_proxy_protocol_inet6_addrs_t)) { return NULL; } in6 = (ngx_proxy_protocol_inet6_addrs_t *) buf; src_sockaddr.sockaddr_in6.sin6_family = AF_INET6; src_sockaddr.sockaddr_in6.sin6_port = 0; memcpy(&src_sockaddr.sockaddr_in6.sin6_addr, in6->src_addr, 16); dst_sockaddr.sockaddr_in6.sin6_family = AF_INET6; dst_sockaddr.sockaddr_in6.sin6_port = 0; memcpy(&dst_sockaddr.sockaddr_in6.sin6_addr, in6->dst_addr, 16); pp->src_port = ngx_proxy_protocol_parse_uint16(in6->src_port); pp->dst_port = ngx_proxy_protocol_parse_uint16(in6->dst_port); socklen = sizeof(struct sockaddr_in6); buf += sizeof(ngx_proxy_protocol_inet6_addrs_t); break; #endif default: ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported address family %ui", family); return end; } pp->src_addr.data = ngx_pnalloc(c->pool, NGX_SOCKADDR_STRLEN); if (pp->src_addr.data == NULL) { return NULL; } pp->src_addr.len = ngx_sock_ntop(&src_sockaddr.sockaddr, socklen, pp->src_addr.data, NGX_SOCKADDR_STRLEN, 0); pp->dst_addr.data = ngx_pnalloc(c->pool, NGX_SOCKADDR_STRLEN); if (pp->dst_addr.data == NULL) { return NULL; } pp->dst_addr.len = ngx_sock_ntop(&dst_sockaddr.sockaddr, socklen, pp->dst_addr.data, NGX_SOCKADDR_STRLEN, 0); ngx_log_debug4(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 src: %V %d, dst: %V %d", &pp->src_addr, pp->src_port, &pp->dst_addr, pp->dst_port); if (buf < end) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 %z bytes of tlv ignored", end - buf); } c->proxy_protocol = pp; return end; }