imapfilter/imapfilter/passwd.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>

#include "config.h"
#include "imapfilter.h"

#ifdef ENCRYPTED_PASSWORDS
#include <openssl/evp.h>
#endif


extern unsigned int flags;
extern account_t *accounts;

#ifdef ENCRYPTED_PASSWORDS
extern char *passphr;
#endif

/*
 * Get password from user interactively.
 */
void
get_password(char *passwd, size_t pwlen)
{
        char *c;

        tty_disable_echo();

        if (fgets(passwd, pwlen, stdin))
                if ((c = strchr(passwd, '\n')))
                        *c = '\0';

        tty_restore();

        putchar('\n');
}


#ifdef ENCRYPTED_PASSWORDS
/*
 * Encrypt and Base64 encode passwords.  Append the MD5 checksum of the
 * passwords before encrypting them.
 */
int
encrypt_passwords(FILE * fd, account_t ** accts)
{
        int i, n;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char buf[ENCRYPTION_BUF];
        unsigned char ebuf[ENCRYPTION_BUF];
        unsigned char bbuf[ENCRYPTION_BUF];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        int mdl, ebufl, bbufl;
        EVP_CIPHER_CTX ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);

        srandom(time(NULL));

        /* Initialization vector. */
        n = 1 + random() % 100000000, 10;
        snprintf(iv, EVP_MAX_IV_LENGTH, "%08d", n);
        fprintf(fd, "%s\n", iv);

        EVP_CIPHER_CTX_init(&ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
            key, NULL);

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
        EVP_EncodeInit(&bctx);

        for (i = 0; accts[i] != NULL; i++) {
                snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
                    accts[i]->username, accts[i]->password);
                EVP_DigestUpdate(&mdctx, buf, strlen(buf));
                EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
                EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);

                fwrite(bbuf, sizeof(char), bbufl, fd);
        }

        EVP_DigestFinal(&mdctx, mdv, &mdl);

        xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);

        /* MD5 checksum of data. */
        for (i = 0; i < mdl; i++)
                snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
                    mdv[i]);

        EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncryptFinal(&ctx, ebuf, &ebufl);

        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncodeFinal(&bctx, bbuf, &bbufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_CIPHER_CTX_cleanup(&ctx);

        return 0;
}


/*
 * Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
 */
int
decrypt_passwords(unsigned char **buf, FILE * fd)
{
        int i, j;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char *c;
        unsigned char ebuf[LINE_MAX];
        unsigned char bbuf[LINE_MAX];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
        int mdl, bufl, ebufl;
        EVP_CIPHER_CTX *ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        j = 1;

        c = *buf = (unsigned char *)smalloc(DECRYPTION_BUF * sizeof(char));
        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
        ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));

        fgets(bbuf, LINE_MAX, fd);

        memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);

        EVP_CIPHER_CTX_init(ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
            1, key, NULL);

        EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
        EVP_DecodeInit(&bctx);

        while (fgets(bbuf, LINE_MAX, fd)) {
                EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
                if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
                        goto fail;

                c += bufl;
                *c = '\0';

                if (c - *buf > DECRYPTION_BUF * j - 64) {
                        i = c - *buf;
                        *buf = (char *)srealloc(*buf, DECRYPTION_BUF * ++j);
                        c = *buf + i;
                        *c = '\0';
                }
        }

        EVP_DecodeFinal(&bctx, ebuf, &ebufl);
        if (!EVP_DecryptFinal(ctx, c, &bufl))
                goto fail;

        c += bufl;
        *c = '\0';

        /* Calculate the MD5 checksum and check if it is correct. */
        if (!(c = strstr(*buf, "\n.\n")))
                goto fail;

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_DigestUpdate(&mdctx, *buf, c - *buf + 1);
        EVP_DigestFinal(&mdctx, mdv, &mdl);

        for (i = 0; i < mdl; i++)
                snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
                    mdv[i]);

        c += 3;

        if (strncmp(c, mdc, 32))
                goto fail;

        EVP_CIPHER_CTX_cleanup(ctx);

        sfree(key);
        sfree(ctx);

        return 0;

fail:
        error("Wrong master passphrase.\n");
        EVP_CIPHER_CTX_cleanup(ctx);
        sfree(*buf);
        sfree(key);
        sfree(ctx);

        return ERROR_DECRYPT;
}


/*
 * Interactive encrypted passwords editor.
 */
void
password_editor(void)
{
        int i, q, n, pn;
        char buf[LINE_MAX];
        char *c;
        char *p[2];
        account_t *a, **accts;

        if (!(flags & FLAG_BLANK_PASSWORD)) {
                error("no candidate passwords for encryption found\n");
                return;
        }
        q = pn = 0;

        for (a = accounts; a != NULL; a = a->next)
                if (a->passwdattr == PASSWORD_NONE ||
                    a->passwdattr == PASSWORD_ENCRYPTED)
                        pn++;

        accts = (account_t **) xmalloc((pn + 1) * sizeof(account_t *));

        memset(accts, 0, (pn + 1) * sizeof(account_t *));

        for (i = 0, a = accounts; a != NULL; a = a->next) {
                if (a->passwdattr == PASSWORD_NONE ||
                    a->passwdattr == PASSWORD_ENCRYPTED)
                        accts[i++] = a;
        }

        do {
                printf("cmd: ");
                fgets(buf, LINE_MAX, stdin);
                c = buf;
                for (;; c++) {
                        if (*c == ' ' || *c == '\t')
                                continue;
                        else if (*c == '?' || *c == 'h')
                                printf("c\tclear a password entry\n"
                                    "e\tedit a password entry\n"
                                    "h\thelp\n"
                                    "l\tlist entries\n"
                                    "p\tchange master password\n"
                                    "q\tquit without saving\n"
                                    "w\tsave changes\n"
                                    "x\tsave and exit\n");
                        else if (*c == 'q')
                                q = 1;
                        else if (*c == 'l')
                                for (i = 0; i < pn; i++)
                                        printf("%d %s %s %s\n", i + 1,
                                            accts[i]->server,
                                            accts[i]->username,
                                            accts[i]->password);
                        else if (*c == 'e') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > pn ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                                printf("Enter new password: ");
                                if (fgets(accts[n - 1]->password, PASSWORD_LEN,
                                        stdin) &&
                                    (c = strchr(accts[n - 1]->password, '\n')))
                                        *c = '\0';
                        } else if (*c == 'c') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > pn ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                        } else if (*c == 'p') {
                                p[0] = (char *)smalloc(PASSPHRASE_LEN);
                                p[1] = (char *)smalloc(PASSPHRASE_LEN);
                                do {
                                        for (i = 0; i < 2; i++) {
                                                printf("Enter %snew master "
                                                    "password: ",
                                                    i ? "again " : "");
                                                get_password(p[i],
                                                    PASSPHRASE_LEN);
                                        }
                                } while (strcmp(p[0], p[1]));
                                xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
                                sfree(p[0]);
                                sfree(p[1]);
                        } else if (*c == 'w' || *c == 's') {
                                store_passwords(accts);
                        } else if (*c == 'x') {
                                store_passwords(accts);
                                q = 1;
                        } else
                                break;
                }
        } while (!q);
}
#endif                          /* ENCRYPTED_PASSWORDS */
1	lefcha	1.1	#include <stdio.h>
2			#include <string.h>
3	lefcha	1.2	#include <stdlib.h>
4			#include <limits.h>
5	lefcha	1.1
6	lefcha	1.2	#include "config.h"
7	lefcha	1.1	#include "imapfilter.h"
8
9	lefcha	1.2	#ifdef ENCRYPTED_PASSWORDS
10			#include <openssl/evp.h>
11			#endif
12	lefcha	1.1
13
14	lefcha	1.5	extern unsigned int flags;
15	lefcha	1.2	extern account_t *accounts;
16
17			#ifdef ENCRYPTED_PASSWORDS
18	lefcha	1.3	extern char *passphr;
19	lefcha	1.2	#endif
20	lefcha	1.1
21			/*
22			* Get password from user interactively.
23			*/
24	lefcha	1.9	void
25			get_password(char *passwd, size_t pwlen)
26	lefcha	1.1	{
27	lefcha	1.9	char *c;
28	lefcha	1.2
29	lefcha	1.9	tty_disable_echo();
30	lefcha	1.8
31	lefcha	1.9	if (fgets(passwd, pwlen, stdin))
32			if ((c = strchr(passwd, '\n')))
33			*c = '\0';
34	lefcha	1.2
35	lefcha	1.9	tty_restore();
36	lefcha	1.1
37	lefcha	1.9	putchar('\n');
38	lefcha	1.1	}
39
40
41	lefcha	1.2	#ifdef ENCRYPTED_PASSWORDS
42	lefcha	1.1	/*
43	lefcha	1.9	* Encrypt and Base64 encode passwords. Append the MD5 checksum of the
44			* passwords before encrypting them.
45	lefcha	1.1	*/
46	lefcha	1.9	int
47	lefcha	1.12	encrypt_passwords(FILE * fd, account_t ** accts)
48	lefcha	1.1	{
49	lefcha	1.13	int i, n;
50	lefcha	1.9	unsigned char iv[EVP_MAX_IV_LENGTH];
51			unsigned char *key;
52			unsigned char buf[ENCRYPTION_BUF];
53			unsigned char ebuf[ENCRYPTION_BUF];
54			unsigned char bbuf[ENCRYPTION_BUF];
55			unsigned char mdv[EVP_MAX_MD_SIZE];
56			int mdl, ebufl, bbufl;
57			EVP_CIPHER_CTX ctx;
58			EVP_MD_CTX mdctx;
59			EVP_ENCODE_CTX bctx;
60
61			key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
62
63			srandom(time(NULL));
64
65			/* Initialization vector. */
66	lefcha	1.13	n = 1 + random() % 100000000, 10;
67			snprintf(iv, EVP_MAX_IV_LENGTH, "%08d", n);
68	lefcha	1.11	fprintf(fd, "%s\n", iv);
69	lefcha	1.9
70			EVP_CIPHER_CTX_init(&ctx);
71
72			EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
73			key, NULL);
74
75			EVP_DigestInit(&mdctx, EVP_md5());
76			EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
77			EVP_EncodeInit(&bctx);
78
79			for (i = 0; accts[i] != NULL; i++) {
80			snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
81			accts[i]->username, accts[i]->password);
82			EVP_DigestUpdate(&mdctx, buf, strlen(buf));
83			EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
84			EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
85	lefcha	1.2
86	lefcha	1.9	fwrite(bbuf, sizeof(char), bbufl, fd);
87			}
88	lefcha	1.6
89	lefcha	1.9	EVP_DigestFinal(&mdctx, mdv, &mdl);
90	lefcha	1.2
91	lefcha	1.9	xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);
92	lefcha	1.8
93	lefcha	1.9	/* MD5 checksum of data. */
94			for (i = 0; i < mdl; i++)
95	lefcha	1.11	snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
96	lefcha	1.9	mdv[i]);
97	lefcha	1.8
98	lefcha	1.9	EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
99			EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
100			fwrite(bbuf, sizeof(char), bbufl, fd);
101	lefcha	1.8
102	lefcha	1.9	EVP_EncryptFinal(&ctx, ebuf, &ebufl);
103	lefcha	1.11
104	lefcha	1.9	EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
105	lefcha	1.11	fwrite(bbuf, sizeof(char), bbufl, fd);
106
107	lefcha	1.9	EVP_EncodeFinal(&bctx, bbuf, &bbufl);
108			fwrite(bbuf, sizeof(char), bbufl, fd);
109	lefcha	1.8
110	lefcha	1.9	EVP_CIPHER_CTX_cleanup(&ctx);
111	lefcha	1.2
112	lefcha	1.9	return 0;
113	lefcha	1.1	}
114
115
116			/*
117	lefcha	1.3	* Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
118	lefcha	1.1	*/
119	lefcha	1.9	int
120			decrypt_passwords(unsigned char *buf, FILE fd)
121	lefcha	1.1	{
122	lefcha	1.9	int i, j;
123			unsigned char iv[EVP_MAX_IV_LENGTH];
124			unsigned char *key;
125			unsigned char *c;
126			unsigned char ebuf[LINE_MAX];
127			unsigned char bbuf[LINE_MAX];
128			unsigned char mdv[EVP_MAX_MD_SIZE];
129			unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
130			int mdl, bufl, ebufl;
131			EVP_CIPHER_CTX *ctx;
132			EVP_MD_CTX mdctx;
133			EVP_ENCODE_CTX bctx;
134
135			j = 1;
136
137			c = buf = (unsigned char )smalloc(DECRYPTION_BUF * sizeof(char));
138			key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
139			ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));
140
141			fgets(bbuf, LINE_MAX, fd);
142
143			memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);
144
145			EVP_CIPHER_CTX_init(ctx);
146
147			EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
148			1, key, NULL);
149
150			EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
151			EVP_DecodeInit(&bctx);
152
153			while (fgets(bbuf, LINE_MAX, fd)) {
154			EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
155			if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
156			goto fail;
157
158			c += bufl;
159			*c = '\0';
160
161			if (c - buf > DECRYPTION_BUF j - 64) {
162			i = c - *buf;
163			buf = (char )srealloc(buf, DECRYPTION_BUF ++j);
164			c = *buf + i;
165			*c = '\0';
166			}
167	lefcha	1.6	}
168	lefcha	1.8
169	lefcha	1.9	EVP_DecodeFinal(&bctx, ebuf, &ebufl);
170			if (!EVP_DecryptFinal(ctx, c, &bufl))
171			goto fail;
172	lefcha	1.2
173	lefcha	1.9	c += bufl;
174			*c = '\0';
175	lefcha	1.6
176	lefcha	1.9	/* Calculate the MD5 checksum and check if it is correct. */
177			if (!(c = strstr(*buf, "\n.\n")))
178			goto fail;
179	lefcha	1.6
180	lefcha	1.9	EVP_DigestInit(&mdctx, EVP_md5());
181			EVP_DigestUpdate(&mdctx, buf, c - buf + 1);
182			EVP_DigestFinal(&mdctx, mdv, &mdl);
183	lefcha	1.8
184	lefcha	1.9	for (i = 0; i < mdl; i++)
185			snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
186			mdv[i]);
187	lefcha	1.8
188	lefcha	1.9	c += 3;
189	lefcha	1.6
190	lefcha	1.9	if (strncmp(c, mdc, 32))
191			goto fail;
192	lefcha	1.2
193	lefcha	1.9	EVP_CIPHER_CTX_cleanup(ctx);
194	lefcha	1.8
195	lefcha	1.9	sfree(key);
196			sfree(ctx);
197	lefcha	1.8
198	lefcha	1.9	return 0;
199	lefcha	1.6
200			fail:
201	lefcha	1.9	error("Wrong master passphrase.\n");
202			EVP_CIPHER_CTX_cleanup(ctx);
203			sfree(*buf);
204			sfree(key);
205			sfree(ctx);
206	lefcha	1.8
207	lefcha	1.9	return ERROR_DECRYPT;
208	lefcha	1.2	}
209
210
211			/*
212			* Interactive encrypted passwords editor.
213			*/
214	lefcha	1.9	void
215			password_editor(void)
216	lefcha	1.2	{
217	lefcha	1.12	int i, q, n, pn;
218	lefcha	1.9	char buf[LINE_MAX];
219			char *c;
220			char *p[2];
221	lefcha	1.12	account_t a, *accts;
222	lefcha	1.9
223			if (!(flags & FLAG_BLANK_PASSWORD)) {
224			error("no candidate passwords for encryption found\n");
225			return;
226	lefcha	1.2	}
227	lefcha	1.12	q = pn = 0;
228
229			for (a = accounts; a != NULL; a = a->next)
230			if (a->passwdattr == PASSWORD_NONE \|\|
231			a->passwdattr == PASSWORD_ENCRYPTED)
232			pn++;
233
234			accts = (account_t *) xmalloc((pn + 1) sizeof(account_t *));
235	lefcha	1.9
236	lefcha	1.12	memset(accts, 0, (pn + 1) * sizeof(account_t *));
237	lefcha	1.9
238	lefcha	1.12	for (i = 0, a = accounts; a != NULL; a = a->next) {
239	lefcha	1.9	if (a->passwdattr == PASSWORD_NONE \|\|
240			a->passwdattr == PASSWORD_ENCRYPTED)
241			accts[i++] = a;
242			}
243
244			do {
245	lefcha	1.10	printf("cmd: ");
246	lefcha	1.9	fgets(buf, LINE_MAX, stdin);
247			c = buf;
248			for (;; c++) {
249			if (c == ' ' \|\| c == '\t')
250			continue;
251			else if (c == '?' \|\| c == 'h')
252			printf("c\tclear a password entry\n"
253			"e\tedit a password entry\n"
254			"h\thelp\n"
255			"l\tlist entries\n"
256			"p\tchange master password\n"
257			"q\tquit without saving\n"
258	lefcha	1.12	"w\tsave changes\n"
259	lefcha	1.9	"x\tsave and exit\n");
260			else if (*c == 'q')
261			q = 1;
262			else if (*c == 'l')
263	lefcha	1.12	for (i = 0; i < pn; i++)
264	lefcha	1.9	printf("%d %s %s %s\n", i + 1,
265			accts[i]->server,
266			accts[i]->username,
267			accts[i]->password);
268			else if (*c == 'e') {
269			n = atoi(++c);
270	lefcha	1.11	if (n == 0 \|\| n < 1 \|\|
271	lefcha	1.12	n > pn \|\|
272	lefcha	1.9	accts[n - 1] == NULL)
273			break;
274			accts[n - 1]->password[0] = '\0';
275			printf("Enter new password: ");
276			if (fgets(accts[n - 1]->password, PASSWORD_LEN,
277			stdin) &&
278			(c = strchr(accts[n - 1]->password, '\n')))
279			*c = '\0';
280			} else if (*c == 'c') {
281			n = atoi(++c);
282	lefcha	1.11	if (n == 0 \|\| n < 1 \|\|
283	lefcha	1.12	n > pn \|\|
284	lefcha	1.9	accts[n - 1] == NULL)
285			break;
286			accts[n - 1]->password[0] = '\0';
287			} else if (*c == 'p') {
288			p[0] = (char *)smalloc(PASSPHRASE_LEN);
289			p[1] = (char *)smalloc(PASSPHRASE_LEN);
290			do {
291			for (i = 0; i < 2; i++) {
292			printf("Enter %snew master "
293			"password: ",
294			i ? "again " : "");
295			get_password(p[i],
296			PASSPHRASE_LEN);
297			}
298			} while (strcmp(p[0], p[1]));
299			xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
300			sfree(p[0]);
301			sfree(p[1]);
302	lefcha	1.12	} else if (c == 'w' \|\| c == 's') {
303	lefcha	1.9	store_passwords(accts);
304			} else if (*c == 'x') {
305			store_passwords(accts);
306			q = 1;
307			} else
308			break;
309			}
310			} while (!q);
311	lefcha	1.1	}
312	lefcha	1.9	#endif /* ENCRYPTED_PASSWORDS */