xref: /third_party/curl/lib/mime.h (revision 13498266)
1#ifndef HEADER_CURL_MIME_H
2#define HEADER_CURL_MIME_H
3/***************************************************************************
4 *                                  _   _ ____  _
5 *  Project                     ___| | | |  _ \| |
6 *                             / __| | | | |_) | |
7 *                            | (__| |_| |  _ <| |___
8 *                             \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
11 *
12 * This software is licensed as described in the file COPYING, which
13 * you should have received as part of this distribution. The terms
14 * are also available at https://curl.se/docs/copyright.html.
15 *
16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
17 * copies of the Software, and permit persons to whom the Software is
18 * furnished to do so, under the terms of the COPYING file.
19 *
20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
21 * KIND, either express or implied.
22 *
23 * SPDX-License-Identifier: curl
24 *
25 ***************************************************************************/
26
27#include "curl_setup.h"
28
29#define MIME_BOUNDARY_DASHES            24  /* leading boundary dashes */
30#define MIME_RAND_BOUNDARY_CHARS        22  /* Nb. of random boundary chars. */
31#define MAX_ENCODED_LINE_LENGTH         76  /* Maximum encoded line length. */
32#define ENCODING_BUFFER_SIZE            256 /* Encoding temp buffers size. */
33
34/* Part flags. */
35#define MIME_USERHEADERS_OWNER  (1 << 0)
36#define MIME_BODY_ONLY          (1 << 1)
37#define MIME_FAST_READ          (1 << 2)
38
39#define FILE_CONTENTTYPE_DEFAULT        "application/octet-stream"
40#define MULTIPART_CONTENTTYPE_DEFAULT   "multipart/mixed"
41#define DISPOSITION_DEFAULT             "attachment"
42
43/* Part source kinds. */
44enum mimekind {
45  MIMEKIND_NONE = 0,            /* Part not set. */
46  MIMEKIND_DATA,                /* Allocated mime data. */
47  MIMEKIND_FILE,                /* Data from file. */
48  MIMEKIND_CALLBACK,            /* Data from `read' callback. */
49  MIMEKIND_MULTIPART,           /* Data is a mime subpart. */
50  MIMEKIND_LAST
51};
52
53/* Readback state tokens. */
54enum mimestate {
55  MIMESTATE_BEGIN,              /* Readback has not yet started. */
56  MIMESTATE_CURLHEADERS,        /* In curl-generated headers. */
57  MIMESTATE_USERHEADERS,        /* In caller's supplied headers. */
58  MIMESTATE_EOH,                /* End of headers. */
59  MIMESTATE_BODY,               /* Placeholder. */
60  MIMESTATE_BOUNDARY1,          /* In boundary prefix. */
61  MIMESTATE_BOUNDARY2,          /* In boundary. */
62  MIMESTATE_CONTENT,            /* In content. */
63  MIMESTATE_END,                /* End of part reached. */
64  MIMESTATE_LAST
65};
66
67/* Mime headers strategies. */
68enum mimestrategy {
69  MIMESTRATEGY_MAIL,            /* Mime mail. */
70  MIMESTRATEGY_FORM,            /* HTTP post form. */
71  MIMESTRATEGY_LAST
72};
73
74/* Content transfer encoder. */
75struct mime_encoder {
76  const char *   name;          /* Encoding name. */
77  size_t         (*encodefunc)(char *buffer, size_t size, bool ateof,
78                               curl_mimepart *part);  /* Encoded read. */
79  curl_off_t     (*sizefunc)(curl_mimepart *part);  /* Encoded size. */
80};
81
82/* Content transfer encoder state. */
83struct mime_encoder_state {
84  size_t         pos;           /* Position on output line. */
85  size_t         bufbeg;        /* Next data index in input buffer. */
86  size_t         bufend;        /* First unused byte index in input buffer. */
87  char           buf[ENCODING_BUFFER_SIZE]; /* Input buffer. */
88};
89
90/* Mime readback state. */
91struct mime_state {
92  enum mimestate state;       /* Current state token. */
93  void *ptr;                  /* State-dependent pointer. */
94  curl_off_t offset;          /* State-dependent offset. */
95};
96
97/* Boundary string length. */
98#define MIME_BOUNDARY_LEN (MIME_BOUNDARY_DASHES + MIME_RAND_BOUNDARY_CHARS)
99
100/* A mime multipart. */
101struct curl_mime {
102  curl_mimepart *parent;           /* Parent part. */
103  curl_mimepart *firstpart;        /* First part. */
104  curl_mimepart *lastpart;         /* Last part. */
105  char boundary[MIME_BOUNDARY_LEN + 1]; /* The part boundary. */
106  struct mime_state state;         /* Current readback state. */
107};
108
109/* A mime part. */
110struct curl_mimepart {
111  curl_mime *parent;               /* Parent mime structure. */
112  curl_mimepart *nextpart;         /* Forward linked list. */
113  enum mimekind kind;              /* The part kind. */
114  unsigned int flags;              /* Flags. */
115  char *data;                      /* Memory data or file name. */
116  curl_read_callback readfunc;     /* Read function. */
117  curl_seek_callback seekfunc;     /* Seek function. */
118  curl_free_callback freefunc;     /* Argument free function. */
119  void *arg;                       /* Argument to callback functions. */
120  FILE *fp;                        /* File pointer. */
121  struct curl_slist *curlheaders;  /* Part headers. */
122  struct curl_slist *userheaders;  /* Part headers. */
123  char *mimetype;                  /* Part mime type. */
124  char *filename;                  /* Remote file name. */
125  char *name;                      /* Data name. */
126  curl_off_t datasize;             /* Expected data size. */
127  struct mime_state state;         /* Current readback state. */
128  const struct mime_encoder *encoder; /* Content data encoder. */
129  struct mime_encoder_state encstate; /* Data encoder state. */
130  size_t lastreadstatus;           /* Last read callback returned status. */
131};
132
133CURLcode Curl_mime_add_header(struct curl_slist **slp, const char *fmt, ...)
134  CURL_PRINTF(2, 3);
135
136#if !defined(CURL_DISABLE_MIME) && (!defined(CURL_DISABLE_HTTP) ||      \
137                                    !defined(CURL_DISABLE_SMTP) ||      \
138                                    !defined(CURL_DISABLE_IMAP))
139
140/* Prototypes. */
141void Curl_mime_initpart(struct curl_mimepart *part);
142void Curl_mime_cleanpart(struct curl_mimepart *part);
143CURLcode Curl_mime_duppart(struct Curl_easy *data,
144                           struct curl_mimepart *dst,
145                           const curl_mimepart *src);
146CURLcode Curl_mime_set_subparts(struct curl_mimepart *part,
147                                struct curl_mime *subparts,
148                                int take_ownership);
149CURLcode Curl_mime_prepare_headers(struct Curl_easy *data,
150                                   struct curl_mimepart *part,
151                                   const char *contenttype,
152                                   const char *disposition,
153                                   enum mimestrategy strategy);
154curl_off_t Curl_mime_size(struct curl_mimepart *part);
155size_t Curl_mime_read(char *buffer, size_t size, size_t nitems,
156                      void *instream);
157CURLcode Curl_mime_rewind(struct curl_mimepart *part);
158const char *Curl_mime_contenttype(const char *filename);
159void Curl_mime_unpause(struct curl_mimepart *part);
160
161#else
162/* if disabled */
163#define Curl_mime_initpart(x)
164#define Curl_mime_cleanpart(x)
165#define Curl_mime_duppart(x,y,z) CURLE_OK /* Nothing to duplicate. Succeed */
166#define Curl_mime_set_subparts(a,b,c) CURLE_NOT_BUILT_IN
167#define Curl_mime_prepare_headers(a,b,c,d,e) CURLE_NOT_BUILT_IN
168#define Curl_mime_size(x) (curl_off_t) -1
169#define Curl_mime_read NULL
170#define Curl_mime_rewind(x) ((void)x, CURLE_NOT_BUILT_IN)
171#define Curl_mime_unpause(x)
172#endif
173
174
175#endif /* HEADER_CURL_MIME_H */
176