1 #include <stdio.h>
2 #ifndef LLHTTP__TEST
3 # include "llhttp.h"
4 #else
5 # define llhttp_t llparse_t
6 #endif /* */
7
8 int llhttp_message_needs_eof(const llhttp_t* parser);
9 int llhttp_should_keep_alive(const llhttp_t* parser);
10
llhttp__before_headers_complete(llhttp_t * parser,const char * p,const char * endp)11 int llhttp__before_headers_complete(llhttp_t* parser, const char* p,
12 const char* endp) {
13 /* Set this here so that on_headers_complete() callbacks can see it */
14 if ((parser->flags & F_UPGRADE) &&
15 (parser->flags & F_CONNECTION_UPGRADE)) {
16 /* For responses, "Upgrade: foo" and "Connection: upgrade" are
17 * mandatory only when it is a 101 Switching Protocols response,
18 * otherwise it is purely informational, to announce support.
19 */
20 parser->upgrade =
21 (parser->type == HTTP_REQUEST || parser->status_code == 101);
22 } else {
23 parser->upgrade = (parser->method == HTTP_CONNECT);
24 }
25 return 0;
26 }
27
28
29 /* Return values:
30 * 0 - No body, `restart`, message_complete
31 * 1 - CONNECT request, `restart`, message_complete, and pause
32 * 2 - chunk_size_start
33 * 3 - body_identity
34 * 4 - body_identity_eof
35 * 5 - invalid transfer-encoding for request
36 */
llhttp__after_headers_complete(llhttp_t * parser,const char * p,const char * endp)37 int llhttp__after_headers_complete(llhttp_t* parser, const char* p,
38 const char* endp) {
39 int hasBody;
40
41 hasBody = parser->flags & F_CHUNKED || parser->content_length > 0;
42 if (parser->upgrade && (parser->method == HTTP_CONNECT ||
43 (parser->flags & F_SKIPBODY) || !hasBody)) {
44 /* Exit, the rest of the message is in a different protocol. */
45 return 1;
46 }
47
48 if (parser->flags & F_SKIPBODY) {
49 return 0;
50 } else if (parser->flags & F_CHUNKED) {
51 /* chunked encoding - ignore Content-Length header, prepare for a chunk */
52 return 2;
53 } else if (parser->flags & F_TRANSFER_ENCODING) {
54 if (parser->type == HTTP_REQUEST && (parser->flags & F_LENIENT) == 0) {
55 /* RFC 7230 3.3.3 */
56
57 /* If a Transfer-Encoding header field
58 * is present in a request and the chunked transfer coding is not
59 * the final encoding, the message body length cannot be determined
60 * reliably; the server MUST respond with the 400 (Bad Request)
61 * status code and then close the connection.
62 */
63 return 5;
64 } else {
65 /* RFC 7230 3.3.3 */
66
67 /* If a Transfer-Encoding header field is present in a response and
68 * the chunked transfer coding is not the final encoding, the
69 * message body length is determined by reading the connection until
70 * it is closed by the server.
71 */
72 return 4;
73 }
74 } else {
75 if (!(parser->flags & F_CONTENT_LENGTH)) {
76 if (!llhttp_message_needs_eof(parser)) {
77 /* Assume content-length 0 - read the next */
78 return 0;
79 } else {
80 /* Read body until EOF */
81 return 4;
82 }
83 } else if (parser->content_length == 0) {
84 /* Content-Length header given but zero: Content-Length: 0\r\n */
85 return 0;
86 } else {
87 /* Content-Length header given and non-zero */
88 return 3;
89 }
90 }
91 }
92
93
llhttp__after_message_complete(llhttp_t * parser,const char * p,const char * endp)94 int llhttp__after_message_complete(llhttp_t* parser, const char* p,
95 const char* endp) {
96 int should_keep_alive;
97
98 should_keep_alive = llhttp_should_keep_alive(parser);
99 parser->finish = HTTP_FINISH_SAFE;
100
101 /* Keep `F_LENIENT` flag between messages, but reset every other flag */
102 parser->flags &= F_LENIENT;
103
104 /* NOTE: this is ignored in loose parsing mode */
105 return should_keep_alive;
106 }
107
108
llhttp_message_needs_eof(const llhttp_t * parser)109 int llhttp_message_needs_eof(const llhttp_t* parser) {
110 if (parser->type == HTTP_REQUEST) {
111 return 0;
112 }
113
114 /* See RFC 2616 section 4.4 */
115 if (parser->status_code / 100 == 1 || /* 1xx e.g. Continue */
116 parser->status_code == 204 || /* No Content */
117 parser->status_code == 304 || /* Not Modified */
118 (parser->flags & F_SKIPBODY)) { /* response to a HEAD request */
119 return 0;
120 }
121
122 /* RFC 7230 3.3.3, see `llhttp__after_headers_complete` */
123 if ((parser->flags & F_TRANSFER_ENCODING) &&
124 (parser->flags & F_CHUNKED) == 0) {
125 return 1;
126 }
127
128 if (parser->flags & (F_CHUNKED | F_CONTENT_LENGTH)) {
129 return 0;
130 }
131
132 return 1;
133 }
134
135
llhttp_should_keep_alive(const llhttp_t * parser)136 int llhttp_should_keep_alive(const llhttp_t* parser) {
137 if (parser->http_major > 0 && parser->http_minor > 0) {
138 /* HTTP/1.1 */
139 if (parser->flags & F_CONNECTION_CLOSE) {
140 return 0;
141 }
142 } else {
143 /* HTTP/1.0 or earlier */
144 if (!(parser->flags & F_CONNECTION_KEEP_ALIVE)) {
145 return 0;
146 }
147 }
148
149 return !llhttp_message_needs_eof(parser);
150 }
151