| /* |
| * Copyright (c) 1983, 1993 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the University of |
| * California, Berkeley and its contributors. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include "tftpsubs.h" |
| |
| /* Simple minded read-ahead/write-behind subroutines for tftp user and |
| server. Written originally with multiple buffers in mind, but current |
| implementation has two buffer logic wired in. |
| |
| Todo: add some sort of final error check so when the write-buffer |
| is finally flushed, the caller can detect if the disk filled up |
| (or had an i/o error) and return a nak to the other side. |
| |
| Jim Guyton 10/85 |
| */ |
| |
| #include <sys/ioctl.h> |
| |
| #define PKTSIZE MAX_SEGSIZE+4 /* should be moved to tftp.h */ |
| |
| int segsize = SEGSIZE; /* Default segsize */ |
| |
| struct bf { |
| int counter; /* size of data in buffer, or flag */ |
| char buf[PKTSIZE]; /* room for data packet */ |
| } bfs[2]; |
| |
| /* Values for bf.counter */ |
| #define BF_ALLOC -3 /* alloc'd but not yet filled */ |
| #define BF_FREE -2 /* free */ |
| /* [-1 .. segsize] = size of data in the data buffer */ |
| |
| static int nextone; /* index of next buffer to use */ |
| static int current; /* index of buffer in use */ |
| |
| /* control flags for crlf conversions */ |
| int newline = 0; /* fillbuf: in middle of newline expansion */ |
| int prevchar = -1; /* putbuf: previous char (cr check) */ |
| |
| static struct tftphdr *rw_init(int); |
| |
| struct tftphdr *w_init() |
| { |
| return rw_init(0); |
| } /* write-behind */ |
| |
| struct tftphdr *r_init() |
| { |
| return rw_init(1); |
| } /* read-ahead */ |
| |
| /* init for either read-ahead or write-behind */ |
| /* x == zero for write-behind, one for read-head */ |
| static struct tftphdr *rw_init(int x) |
| { |
| newline = 0; /* init crlf flag */ |
| prevchar = -1; |
| bfs[0].counter = BF_ALLOC; /* pass out the first buffer */ |
| current = 0; |
| bfs[1].counter = BF_FREE; |
| nextone = x; /* ahead or behind? */ |
| return (struct tftphdr *)bfs[0].buf; |
| } |
| |
| /* Have emptied current buffer by sending to net and getting ack. |
| Free it and return next buffer filled with data. |
| */ |
| int readit(FILE * file, struct tftphdr **dpp, int convert) |
| { |
| struct bf *b; |
| |
| bfs[current].counter = BF_FREE; /* free old one */ |
| current = !current; /* "incr" current */ |
| |
| b = &bfs[current]; /* look at new buffer */ |
| if (b->counter == BF_FREE) /* if it's empty */ |
| read_ahead(file, convert); /* fill it */ |
| /* assert(b->counter != BF_FREE);*//* check */ |
| *dpp = (struct tftphdr *)b->buf; /* set caller's ptr */ |
| return b->counter; |
| } |
| |
| /* |
| * fill the input buffer, doing ascii conversions if requested |
| * conversions are lf -> cr,lf and cr -> cr, nul |
| */ |
| void read_ahead(FILE * file, int convert) |
| { |
| int i; |
| char *p; |
| int c; |
| struct bf *b; |
| struct tftphdr *dp; |
| |
| b = &bfs[nextone]; /* look at "next" buffer */ |
| if (b->counter != BF_FREE) /* nop if not free */ |
| return; |
| nextone = !nextone; /* "incr" next buffer ptr */ |
| |
| dp = (struct tftphdr *)b->buf; |
| |
| if (convert == 0) { |
| b->counter = read(fileno(file), dp->th_data, segsize); |
| return; |
| } |
| |
| p = dp->th_data; |
| for (i = 0; i < segsize; i++) { |
| if (newline) { |
| if (prevchar == '\n') |
| c = '\n'; /* lf to cr,lf */ |
| else |
| c = '\0'; /* cr to cr,nul */ |
| newline = 0; |
| } else { |
| c = getc(file); |
| if (c == EOF) |
| break; |
| if (c == '\n' || c == '\r') { |
| prevchar = c; |
| c = '\r'; |
| newline = 1; |
| } |
| } |
| *p++ = c; |
| } |
| b->counter = (int)(p - dp->th_data); |
| } |
| |
| /* Update count associated with the buffer, get new buffer |
| from the queue. Calls write_behind only if next buffer not |
| available. |
| */ |
| int writeit(FILE * file, struct tftphdr **dpp, int ct, int convert) |
| { |
| bfs[current].counter = ct; /* set size of data to write */ |
| current = !current; /* switch to other buffer */ |
| if (bfs[current].counter != BF_FREE) /* if not free */ |
| (void)write_behind(file, convert); /* flush it */ |
| bfs[current].counter = BF_ALLOC; /* mark as alloc'd */ |
| *dpp = (struct tftphdr *)bfs[current].buf; |
| return ct; /* this is a lie of course */ |
| } |
| |
| /* |
| * Output a buffer to a file, converting from netascii if requested. |
| * CR,NUL -> CR and CR,LF => LF. |
| * Note spec is undefined if we get CR as last byte of file or a |
| * CR followed by anything else. In this case we leave it alone. |
| */ |
| int write_behind(FILE * file, int convert) |
| { |
| char *buf; |
| int count; |
| int ct; |
| char *p; |
| int c; /* current character */ |
| struct bf *b; |
| struct tftphdr *dp; |
| |
| b = &bfs[nextone]; |
| if (b->counter < -1) /* anything to flush? */ |
| return 0; /* just nop if nothing to do */ |
| |
| count = b->counter; /* remember byte count */ |
| b->counter = BF_FREE; /* reset flag */ |
| dp = (struct tftphdr *)b->buf; |
| nextone = !nextone; /* incr for next time */ |
| buf = dp->th_data; |
| |
| if (count <= 0) |
| return -1; /* nak logic? */ |
| |
| if (convert == 0) |
| return write(fileno(file), buf, count); |
| |
| p = buf; |
| ct = count; |
| while (ct--) { /* loop over the buffer */ |
| c = *p++; /* pick up a character */ |
| if (prevchar == '\r') { /* if prev char was cr */ |
| if (c == '\n') /* if have cr,lf then just */ |
| fseek(file, -1, 1); /* smash lf on top of the cr */ |
| else if (c == '\0') /* if have cr,nul then */ |
| goto skipit; /* just skip over the putc */ |
| /* else just fall through and allow it */ |
| } |
| putc(c, file); |
| skipit: |
| prevchar = c; |
| } |
| return count; |
| } |
| |
| /* When an error has occurred, it is possible that the two sides |
| * are out of synch. Ie: that what I think is the other side's |
| * response to packet N is really their response to packet N-1. |
| * |
| * So, to try to prevent that, we flush all the input queued up |
| * for us on the network connection on our host. |
| * |
| * We return the number of packets we flushed (mostly for reporting |
| * when trace is active). |
| */ |
| |
| int synchnet(int f) |
| { /* socket to flush */ |
| int pktcount = 0; |
| char rbuf[PKTSIZE]; |
| union sock_addr from; |
| socklen_t fromlen; |
| fd_set socketset; |
| struct timeval notime; |
| |
| while (1) { |
| notime.tv_sec = notime.tv_usec = 0; |
| |
| FD_ZERO(&socketset); |
| FD_SET(f, &socketset); |
| |
| if (select(f, &socketset, NULL, NULL, ¬ime) <= 0) |
| break; /* Nothing to read */ |
| |
| /* Otherwise drain the packet */ |
| pktcount++; |
| fromlen = sizeof(from); |
| (void)recvfrom(f, rbuf, sizeof(rbuf), 0, |
| &from.sa, &fromlen); |
| } |
| |
| return pktcount; /* Return packets drained */ |
| } |
| |
| int pick_port_bind(int sockfd, union sock_addr *myaddr, |
| unsigned int port_range_from, |
| unsigned int port_range_to) |
| { |
| unsigned int port, firstport; |
| int port_range = 0; |
| |
| if (port_range_from != 0 && port_range_to != 0) { |
| port_range = 1; |
| } |
| |
| firstport = port_range |
| ? port_range_from + rand() % (port_range_to - port_range_from + 1) |
| : 0; |
| |
| port = firstport; |
| |
| do { |
| sa_set_port(myaddr, htons(port)); |
| if (bind(sockfd, &myaddr->sa, SOCKLEN(myaddr)) < 0) { |
| /* Some versions of Linux return EINVAL instead of EADDRINUSE */ |
| if (!(port_range && (errno == EINVAL || errno == EADDRINUSE))) |
| return -1; |
| |
| /* Normally, we shouldn't have to loop, but some situations involving |
| aborted transfers make it possible. */ |
| } else { |
| return 0; |
| } |
| |
| port++; |
| if (port > port_range_to) |
| port = port_range_from; |
| } while (port != firstport); |
| |
| return -1; |
| } |
| |
| int |
| set_sock_addr(char *host,union sock_addr *s, char **name) |
| { |
| struct addrinfo *addrResult; |
| struct addrinfo hints; |
| int err; |
| |
| memset(&hints, 0, sizeof(hints)); |
| hints.ai_family = s->sa.sa_family; |
| hints.ai_flags = AI_CANONNAME | AI_ADDRCONFIG; |
| hints.ai_socktype = SOCK_DGRAM; |
| hints.ai_protocol = IPPROTO_UDP; |
| err = getaddrinfo(strip_address(host), NULL, &hints, &addrResult); |
| if (err) |
| return err; |
| if (addrResult == NULL) |
| return EAI_NONAME; |
| memcpy(s, addrResult->ai_addr, addrResult->ai_addrlen); |
| if (name) { |
| if (addrResult->ai_canonname) |
| *name = xstrdup(addrResult->ai_canonname); |
| else |
| *name = xstrdup(host); |
| } |
| freeaddrinfo(addrResult); |
| return 0; |
| } |
| |
| #ifdef HAVE_IPV6 |
| int is_numeric_ipv6(const char *p) |
| { |
| /* A numeric IPv6 address consist at least of 2 ':' and |
| * it may have sequences of hex-digits and maybe contain |
| * a '.' from a IPv4 mapped address and maybe is enclosed in [] |
| * we do not check here, if it is a valid IPv6 address |
| * only if is something like a numeric IPv6 address or something else |
| */ |
| int colon = 0; |
| int dot = 0; |
| int bracket = 0; |
| char c; |
| |
| if (!p) |
| return 0; |
| |
| if (*p == '[') { |
| bracket = 1; |
| p++; |
| } |
| |
| while ((c = *p++) && c != ']') { |
| switch (c) { |
| case ':': |
| colon++; |
| break; |
| case '.': |
| dot++; |
| break; |
| case '0': case '1': case '2': case '3': case '4': |
| case '5': case '6': case '7': case '8': case '9': |
| case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': |
| case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': |
| break; |
| default: |
| return 0; /* Invalid character */ |
| } |
| } |
| |
| if (colon < 2 || colon > 7) |
| return 0; |
| |
| if (dot) { |
| /* An IPv4-mapped address in dot-quad form will have 3 dots */ |
| if (dot != 3) |
| return 0; |
| /* The IPv4-mapped address takes the space of one colon */ |
| if (colon > 6) |
| return 0; |
| } |
| |
| /* If bracketed, must be closed, and vice versa */ |
| if (bracket ^ (c == ']')) |
| return 0; |
| |
| /* Otherwise, assume we're okay */ |
| return 1; |
| } |
| |
| /* strip [] from numeric IPv6 addreses */ |
| |
| char *strip_address(char *addr) |
| { |
| char *p; |
| |
| if (is_numeric_ipv6(addr) && (*addr == '[')) { |
| p = addr + strlen(addr); |
| p--; |
| if (*p == ']') { |
| *p = 0; |
| addr++; |
| } |
| } |
| return addr; |
| } |
| #endif |
