comm.c revision 94334
1/* 2 * Copyright (c) 1999-2002 Sendmail, Inc. and its suppliers. 3 * All rights reserved. 4 * 5 * By using this file, you agree to the terms and conditions set 6 * forth in the LICENSE file which can be found at the top level of 7 * the sendmail distribution. 8 * 9 */ 10 11#include <sm/gen.h> 12SM_RCSID("@(#)$Id: comm.c,v 8.54 2002/03/06 16:03:26 ca Exp $") 13 14#include "libmilter.h" 15#include <sm/errstring.h> 16 17#define FD_Z FD_ZERO(&readset); \ 18 FD_SET((unsigned int) sd, &readset); \ 19 FD_ZERO(&excset); \ 20 FD_SET((unsigned int) sd, &excset) 21 22/* 23** MI_RD_CMD -- read a command 24** 25** Parameters: 26** sd -- socket descriptor 27** timeout -- maximum time to wait 28** cmd -- single character command read from sd 29** rlen -- pointer to length of result 30** name -- name of milter 31** 32** Returns: 33** buffer with rest of command 34** (malloc()ed here, should be free()d) 35** hack: encode error in cmd 36*/ 37 38char * 39mi_rd_cmd(sd, timeout, cmd, rlen, name) 40 socket_t sd; 41 struct timeval *timeout; 42 char *cmd; 43 size_t *rlen; 44 char *name; 45{ 46 ssize_t len; 47 mi_int32 expl; 48 ssize_t i; 49 fd_set readset, excset; 50 int ret; 51 int save_errno; 52 char *buf; 53 char data[MILTER_LEN_BYTES + 1]; 54 55 *cmd = '\0'; 56 *rlen = 0; 57 58 if (sd >= FD_SETSIZE) 59 { 60 smi_log(SMI_LOG_ERR, "%s: fd %d is larger than FD_SETSIZE %d", 61 name, sd, FD_SETSIZE); 62 *cmd = SMFIC_SELECT; 63 return NULL; 64 } 65 66 FD_Z; 67 i = 0; 68 while ((ret = select(sd + 1, &readset, NULL, &excset, timeout)) >= 1) 69 { 70 if (FD_ISSET(sd, &excset)) 71 { 72 *cmd = SMFIC_SELECT; 73 return NULL; 74 } 75 76 len = MI_SOCK_READ(sd, data + i, sizeof data - i); 77 if (MI_SOCK_READ_FAIL(len)) 78 { 79 smi_log(SMI_LOG_ERR, 80 "%s, mi_rd_cmd: read returned %d: %s", 81 name, len, sm_errstring(errno)); 82 *cmd = SMFIC_RECVERR; 83 return NULL; 84 } 85 if (len == 0) 86 { 87 *cmd = SMFIC_EOF; 88 return NULL; 89 } 90 if (len >= (ssize_t) sizeof data - i) 91 break; 92 i += len; 93 FD_Z; 94 } 95 if (ret == 0) 96 { 97 *cmd = SMFIC_TIMEOUT; 98 return NULL; 99 } 100 else if (ret < 0) 101 { 102 smi_log(SMI_LOG_ERR, 103 "%s: mi_rd_cmd: select returned %d: %s", 104 name, ret, sm_errstring(errno)); 105 *cmd = SMFIC_RECVERR; 106 return NULL; 107 } 108 109 *cmd = data[MILTER_LEN_BYTES]; 110 data[MILTER_LEN_BYTES] = '\0'; 111 (void) memcpy((void *) &expl, (void *) &(data[0]), MILTER_LEN_BYTES); 112 expl = ntohl(expl) - 1; 113 if (expl <= 0) 114 return NULL; 115 if (expl > MILTER_CHUNK_SIZE) 116 { 117 *cmd = SMFIC_TOOBIG; 118 return NULL; 119 } 120#if _FFR_ADD_NULL 121 buf = malloc(expl + 1); 122#else /* _FFR_ADD_NULL */ 123 buf = malloc(expl); 124#endif /* _FFR_ADD_NULL */ 125 if (buf == NULL) 126 { 127 *cmd = SMFIC_MALLOC; 128 return NULL; 129 } 130 131 i = 0; 132 FD_Z; 133 while ((ret = select(sd + 1, &readset, NULL, &excset, timeout)) == 1) 134 { 135 if (FD_ISSET(sd, &excset)) 136 { 137 *cmd = SMFIC_SELECT; 138 free(buf); 139 return NULL; 140 } 141 len = MI_SOCK_READ(sd, buf + i, expl - i); 142 if (MI_SOCK_READ_FAIL(len)) 143 { 144 smi_log(SMI_LOG_ERR, 145 "%s: mi_rd_cmd: read returned %d: %s", 146 name, len, sm_errstring(errno)); 147 ret = -1; 148 break; 149 } 150 if (len == 0) 151 { 152 *cmd = SMFIC_EOF; 153 free(buf); 154 return NULL; 155 } 156 if (len > expl - i) 157 { 158 *cmd = SMFIC_RECVERR; 159 free(buf); 160 return NULL; 161 } 162 if (len >= expl - i) 163 { 164 *rlen = expl; 165#if _FFR_ADD_NULL 166 /* makes life simpler for common string routines */ 167 buf[expl] = '\0'; 168#endif /* _FFR_ADD_NULL */ 169 return buf; 170 } 171 i += len; 172 FD_Z; 173 } 174 175 save_errno = errno; 176 free(buf); 177 178 /* select returned 0 (timeout) or < 0 (error) */ 179 if (ret == 0) 180 { 181 *cmd = SMFIC_TIMEOUT; 182 return NULL; 183 } 184 if (ret < 0) 185 { 186 smi_log(SMI_LOG_ERR, 187 "%s: mi_rd_cmd: select returned %d: %s", 188 name, ret, sm_errstring(save_errno)); 189 *cmd = SMFIC_RECVERR; 190 return NULL; 191 } 192 *cmd = SMFIC_UNKNERR; 193 return NULL; 194} 195/* 196** MI_WR_CMD -- write a cmd to sd 197** 198** Parameters: 199** sd -- socket descriptor 200** timeout -- maximum time to wait (currently unused) 201** cmd -- single character command to write 202** buf -- buffer with further data 203** len -- length of buffer (without cmd!) 204** 205** Returns: 206** MI_SUCCESS/MI_FAILURE 207*/ 208 209/* 210** we don't care much about the timeout here, it's very long anyway 211** FD_SETSIZE is only checked in mi_rd_cmd. 212** XXX l == 0 ? 213*/ 214 215#define MI_WR(data) \ 216 while (sl > 0) \ 217 { \ 218 FD_ZERO(&wrtset); \ 219 FD_SET((unsigned int) sd, &wrtset); \ 220 ret = select(sd + 1, NULL, &wrtset, NULL, timeout); \ 221 if (ret == 0) \ 222 return MI_FAILURE; \ 223 if (ret < 0) \ 224 { \ 225 if (errno == EINTR) \ 226 continue; \ 227 else \ 228 return MI_FAILURE; \ 229 } \ 230 l = MI_SOCK_WRITE(sd, (void *) ((data) + i), sl); \ 231 if (l < 0) \ 232 { \ 233 if (errno == EINTR) \ 234 continue; \ 235 else \ 236 return MI_FAILURE; \ 237 } \ 238 i += l; \ 239 sl -= l; \ 240 } 241 242int 243mi_wr_cmd(sd, timeout, cmd, buf, len) 244 socket_t sd; 245 struct timeval *timeout; 246 int cmd; 247 char *buf; 248 size_t len; 249{ 250 size_t sl, i; 251 ssize_t l; 252 mi_int32 nl; 253 int ret; 254 fd_set wrtset; 255 char data[MILTER_LEN_BYTES + 1]; 256 257 if (len > MILTER_CHUNK_SIZE) 258 return MI_FAILURE; 259 nl = htonl(len + 1); /* add 1 for the cmd char */ 260 (void) memcpy(data, (void *) &nl, MILTER_LEN_BYTES); 261 data[MILTER_LEN_BYTES] = (char) cmd; 262 i = 0; 263 sl = MILTER_LEN_BYTES + 1; 264 265 /* use writev() instead to send the whole stuff at once? */ 266 267 MI_WR(data); 268 if (len > 0 && buf == NULL) 269 return MI_FAILURE; 270 if (len == 0 || buf == NULL) 271 return MI_SUCCESS; 272 i = 0; 273 sl = len; 274 MI_WR(buf); 275 return MI_SUCCESS; 276} 277